FYI, I was going to report that Amazon got them in stock, but they're now already out again. They're showing that they expect a shipment in on 10/10, though, so that's not so bad. But it seems like these things are definitely selling (out) well. I'm kicking myself a bit, because I was going to pay the extra $3.99 for delivery on Saturday, but I missed out. I missed out because I wanted to first hook up my one Apple TV to every room in the house to look for any particular issues. That test was a success (more on that in a bit), but by the time I pulled up Amazon's site, they were no longer available for Saturday delivery. This 2nd unit will be for my daughter's room. She's been tying up our room lately making use of Netflix. No big deal, though...she'll just have to wait a few more days.
As for my testing, here are the rooms I tried it on, each with some unique "features" which I was concerned could pose problems for the Apple TV, along with my results. I'm posting this because of some rumors/concerns that are floating around the web with the Apple TV not working with a lot of older TVs, so as to allay some concerns:
1) First room was my daughter's room. This has a Vizio LCD TV (model VX37L). I believe this is the oldest 16:9 set in my house. It has a native resolution of 1366x768, which I worried could cause scaling problems, but I believe this is a common native resolution for "720p" TVs. As a somewhat older TV, I also wasn't sure what version the HDMI input was, and I've read some people claim that the Apple TV required an HDMI 1.3 (spoiler alert: this is definitely false). In this room, I honestly didn't inspect the PQ too closely, because I knew that my daughter wouldn't concern herself with such things, so I sat at a normal viewing distance and looked for any stutter/judder issues. Everything looked fine. The other concern with this room is that it's in the lowest level of our house, and so it *might* have had issues pulling in a strong 802.11n signal. We have an open floorplan post & beam house with a two-story living room and I recently purchased an Apple AirPort Extreme wireless router (802.11n with dual radios that can work independently), and it's located in the loft which overlooks the living room, and my daughter's room is directly below the living room. So it has a fairly clear shot (with just the living room floor in between), so I wasn't expecting any major issues. In fact, the Apple TV's general info screen reported full bars.
2) Next room was the living room. It has a Panasonic 50" 720p plasma (model TH-C50HD18). I believe this also has a native resolution of 1366x768 (I couldn't find it in the manual, but I've found some online sources that indicate as such and I seem to recall that it might have listed it on the box when I bought it). I believe that resolution is/was less common among plasmas (they used to have a native 1280x720, and perhaps some/most still do). Not sure of the version of HDMI on this one, either, but it's only about a 2.5 year old set. No major concerns about this room, other than the potential stutter/judder issue. From a normal seating distance, it looked fine. This is not a room where I choose to watch movies (when given a choice) but is a room where a good deal of TV is watched (by everyone but me). Again, no bothersome stutter/judder issues that I could detect, which is good since there did not appear to be any menu options for tweaking 3:2 pull-down logic.
3) The last room I tested was my home theater which has an older Panasonic 720p (native 1280x720) LCD projector. This room was my biggest concern because both the projector and A/V receiver (a JVC RX-D401 digital receiver) are fairly old, and I'm pretty sure that one or both of them have an early HDMI input (v1.1, I believe). Also, it's my understanding that this projector does something stupid and takes incoming 720p signals and adjusts the resolution so as to overscan the image, so even though you're feeding it a 1280x720 signal, and the projector has a native 1280x720 resolution, it ends up upscaling and then cropping it somewhat (if I fully understand the situation). I've read online that some people have had trouble getting 5.1 audio to work (in general), as well as more specifically that their problem may have had to do with the version of HDMI their receiver had. My one issue in testing this room is that it has horrible light control, so in testing it this morning, the screen was pretty washed out. In any case, everything appeared to work fine. I saw no stutter/judder issues, and the receiver immediately played my test video's 5.1 multichannel audio. It did not report it as Dolby Digital, but I think that's because I had manually set it to multichannel mode (or maybe automatic mode) to support lossless audio from my Blu-ray player or Acer Revo (where MPC-HC could decode Dolby TrueHD and pass it as lossless multichannel audio). In any case, switching through the receiver's Surround Sound settings and forcing it into Dolby Digital mode worked fine, with the receiver now reporting the incoming signal as such.
4) This last one is actually the first room I've been using over the last week to test things out. It's the master bedroom and has a Sharp Aquos 52" 1080p LCD. This room gave me trouble initially with the stutter/judder issues, which I believe I've solved by turning *OFF* all of the fancy-shmancy logic that the set has (on by default) for fine motion (whatever that means) and film mode (3:2 pull-down).
In all rooms I used the Apple TV wirelessly, though in reality my bedroom and the theater room will be hard-wired. The living room and my daughter's room will use wireless due to the difficulty of running ethernet to those two rooms. While having to convert 1080p Blu-ray rips with lossless audio to 720p .m4v files with AC3 (Dolby Digital) audio is a pain, and some PQ and AQ loss will result, one advantage is that I won't need to worry about streaming the resulting 4GB (or less) files wirelessly. With 802.11n and the Apple TV's 8GB buffer, the files should get loaded quickly with enough buffer so as to prevent skipping. And I'll be able to do that with multiple rooms simultaneously. Try that with a 20GB (or bigger) Blu-ray rip. Streaming just one of those wirelessly over 802.11n is likely asking for some trouble, but streaming multiple files simultaneously? Granted, I haven't actually tested this out, but in theory I shouldn't have a problem.
A more realistic issue will be that during prime-time (with Comcast's cable modem line getting hit and the supposed 14GB download speed not delivering), combined with multiple rooms trying to stream Netflix simultaneously (or trying to download an iTunes movie or show), we could have long wait times (for iTunes) or decreased PQ from Netflix. I'll have to see how that goes. For me, though, my main concern with these boxes is the ability to stream my own content across the house well, and for my daughter (who won't care too much about decreased PQ) to watch kid's shows/movies from Netflix.
I expect we'll make use of Netflix for some casual movie/show watching in our bedroom (where the PQ will be annoying due to our fairly close viewing distance to a rather large TV) and the living room (where noticing PQ issues will be less of a concern). I'll try to avoid watching Netflix in the theater room, because of the PQ issues and (until they add it) lack of 5.1 audio.
I bought a TiVo HD from Blockbuster recently (only $100) to give to our daughter for her birthday, but hadn't set it up yet. I was still not feeling great about paying yet another $10-13/month for their service (we already have two in operation). Then the Apple TV hit and I figured that live TV combined with Netflix could meet her needs, and based on her testing of the Apple TV in our bedroom this past week, that seems to be a success. So now I'll be ebaying/craigslisting that unopened TiVo HD.
My next baby step may be to try to convince my wife to shut down the TiVo service on our living room box, but first I'll need to get her (and my father-in-law) to get used to using the Apple TV in that room. That will require training them on using the Netflix functionality, as well as me ripping/converting more TV shows.
Another thought I had was to try to use a computer to DVR shows (for no monthly fee) and convert those to .mp4/m4v files. A few issues with that are that I'll only be able to get the clear QAM channels (local networks), we'll lose the pause feature, and they'll have to wait to watch the shows. Another possibility will be to leave one TiVo in action (in our bedroom), so my wife can be happier, and pull some of those shows off nightly via computer to convert them to mp4/m4v files.