will the disappearance of unlimited data plans save Sirius XM for the time being?

I don't know that it'll save them or if they were still around if it'd kill them.

Streaming music in your vehicle is nice but:
- I don't think most people really want to bother plugging a device in. They may carry an iPod plugged into their car most of the time but for something like a phone they don't want to plug/unplug as they're so used to just getting in, starting, and driving off. People are generally lazy. Yes, you'll have geeky guys (both stereo guys and computer guys) doing this and a smattering of younger folks but, long term, I think they'll just go lazy and go back to the radio or the iPod that is (semi) permanently attached.
- you kind of need a dock. Oddly the XM Skydock works really well for streaming. You generally want to be able to look at the screen to skip/rate the sucky/good songs. That doesn't work too well when it's just plugged in laying in the passenger's seat.
- Wires are an issue. I don't think people (average) are too keen on wires being strewn about their dash. Sirius/XM radios have this problem, too, as does GPS. It all starts to get very cluttered very fast.
- Data usage will be a problem. The mobile companies seem to be fairly stuck on charging us a lot of money for just a few gigs of data. If you were to compare this to SMS plans you'll likely see them get more expensive with popularity, not less.
- Sirius/XM works everywhere. Your phone's streaming doesn't (not a problem for Slacker users who cache the content, though).

Overall it's all pretty interesting and I like the choice. Sirius/XM basically provides these benefits:
- variety of channels (not necessarily songs)
- works (nearly) everywhere
- no data usage fees so flat rate per month

It doesn't win on:
- sound quality
- variety of music

I think Sirius/XM has basically made 'cable for your car'. It's not exciting. Some people get it. Others don't want to pay for it. It's utilitarian in nature. Years back people were buzzing about it's quality and variety (I was one of them). Not any longer. Go to a satellite radio forum and see what they're talking about. Answer: Anything and everything but satellite radio (with the exception of the one thread here that won't die about their service being up and how do they get a cheap rate - the answer is the same every time - threaten to cancel or cancel and wait for them to make you an offer - still the thread lives).

I ditched XM radio two years gave my radio to my uncle and switched to Internet Radio (DI.fm/Sky.fm/Jazzradio Premium/Slacker & AOL Radio/TuneIn Radio Pro) and never looked back. Satellite radio just leaves a bad taste in my mouth however I do agree that you need WiFi & Cell service to listen to online radio. Cell service is spotty in many areas and has caps. Even though I still don't like Satellite Radio with it's horrible sound quality and shallow playlists but it is your only choice where you have no internet access but I end up turning it off after 20 minutes anyway..

I am a truck driver, if it wasn't for O&A and Ron and Fez, I would cancel my XM sub. Howard Stern is on a Sirius Lifetime radio so I wouldn't be without Sat radio or Howard, but I have a backlog of Podcasts, so content is not an issue even if I didn't have that lifetime radio.
Many truckers have Sat. radio but I do see more and more using podcasts and internet radio for content as they drive. So IMO Sat. radio is viable and safe from competitors, for the time being...

I do wonder what happened to the nationwide high speed internet we were "promised" after the HDTV switchover and all that bandwidth was cleared up.

NO, because unlimited data plans are reappearing. I just converted to T-mobile's unlimited 4G. Coincidentally, I received an e-mail from Sirius/XM for a free month trial of their smartphone app / tablet / computer streaming service. Great, I always wanted to try it for myself.

Sirius/XM will definitely not be getting my money for a subscription - and after testing it for a week I have already uninstalled the app. The main reasons are listed here, bearing in mind that I am mostly comparing with Tune-In Radio Pro (which I use the most) and Pandora.

1. Channel selection sucks.

2. Even when they are playing music I like, playlists are limited and repetitive. I thought it should be different than terrestrial radio? More dumbass me for thinking so.

3. The app forgot my login info after a week. It was easier for me to uninstall the app than enter my credentials, because I just didn't care if I ever used it again.

4. Taking the cake, the app stopped playing the other day and I thought what!? Activated my phone to see a message indicating that it had stopped due to inactivity. HELLO!! I listen to music all day long at work, and I shouldn't have to interact with my phone to keep it coming. BOGUS!! That irritated me more than anything else about the Sirius/XM streaming service. EPIC FAIL, as my son would say.

Bear in mind that I am not nor have I ever been a Stern fan, so that doesn't factor into my verdict.

With Tune-In Radio Pro I have a MUCH wider selection of music, more stations, no inactivity stoppages, plus the ability to record the stream.

BTW, I can stream Netflix at home on T-mobile's 4G network using my smartphone as a wireless hotspot. Not something I do regularly, but an interesting test of capacity and explanatory as to why I get great quality audio with Tune-In Radio Pro.

Thanks to Sirius/XM for the free trial, but no dice, no way.