I recently downloaded the 3.0 firmware update via Ethernet to see if there were any noticeable changes with my HD-A35. The DL took about eighteen minutes over DSL and the player shut itself down when it finished. I powered the player back up to make sure it was still functioning and it was fine. I shut down the A35 and unplugged the unit for about a minute then powered it back up again.
PROBLEMS/ANNOYANCES I HAVE OBSERVED:
It still takes a long time to boot up and also does not instantly open the tray when the button on the unit is pressed if it has not booted yet. More of an annoyance than a problem as my previous DVD player came to life and opened the tray instantly upon pressing the eject button. I believe that this should be standard on any high profile DVD player.
I still have tons of SD DVDs that I enjoy watching. I find it odd that there seems to be a zoom button missing from the remote. Only HD-DVDs that support this feature (using the A-B-C-D buttons) will allow zooming. I would think that the A-B-C-D buttons would be able to be used for zooming during SD DVD playback. My other DVD player was so old, it didn't have progressive playback capabilities or a zoom feature either. Try to find any DVD player today lacking either of these features.
I think this next problem is absolutely absurd: The VIDEO output setting in the player affects the AUDIO output.

The A35 has the capability of bitstreaming the audio to a receiver for it to decode the raw signal over an HDMI connection. I changed the settings in the player and my Onkyo TX-SR605 for weeks as I tried to stream DD+, Dolby True HD, and DTS-MA. All I got was a stereo PCM signal. Other audio formats from SD DVDs such as DD 5.1 and standard DTS stream just fine. It wasn't until I set up a progressive capable monitor and switched the settings from 480i to ANYTHING ELSE was I able to get it to bitstream properly. Even though the setup menu APPEARS that everything should be working properly, the manual makes no mention of this oddity. Surprisingly, the Toshiba Customer Service Representative stated that the player was never meant to be set up in this way.
Then why can I make these choices from the setup menu? 
Also, I noticed that the player did not prompt me for the date and time after installing 3.0. I believe that Toshiba was tired of getting the "How do I enter the date and time on my player?" question. And yes, you STILL have to enter the date and time with the numeric keypad. Oh wait - the choice to enter AM or PM can be selected with the arrow keys.

FW 3.0 FIXES:
As of this writing, Toshiba has not posted what this update from 2.0 to 3.0 specifically fixes. I have read that it has successfully allowed complete playback of certain problem discs for some people. I noticed that with 2.0, my SD DVDs froze quite often when pressing fast-forward then rewind too quickly. At least you can resume playback after pressing stop with SD DVDs. (Don't get me started with that deficiency of HD-DVD...) This problem seems to have disappeared with the release of 3.0. That is - I tried to replicate the intermittent problem with many discs and they all kept playing fine.

I have personally not experienced any playback issues where a disc failed to play at certain parts of a movie.
Unfortunately, I can neither confirm nor deny the presence of "jaggies" with FW 3.0 as I do not have a 1080p/24 capable display.
So am I a picky nerd that feels the need to dissect a piece of technology, or just someone that expects a product to work the way it was meant to? I'm sure every person reading this feels the same way. *continue nodding*
Here's to the next firmware update! Maybe the stuff that matters will get fixed eventually.