I've been running beta 2 for about 2 days now, and wanted to chime in on some of the bugs I'm getting:
SMS works with 3rd party app, but I'm getting the "no APN on device" toast frequently, although I have set the APN manually in textra, which has allowed me to send/receive MMS. I can't seem to manually set them in CM settings though. Any changes I make there don't stick.
YouTube is not working for me, it loads search results, but when I try to play a video it just tells me the connection with sever was lost. This happens on Wi-Fi and 3g.
I too am experiencing the slight slowdown of audio playback over Bluetooth. It's minimal, but just enough to notice. Thought I was going nuts until I read through the thread and saw that some one else experienced this too.
I realize this is an extremely early beta build, and you are doing a fantastic job! Thank you for your hard work! I'll see if I can get some logs for you if you think that would help with this. I'm not the best at fixing these kinds of things (willing to learn though), but boy am I good at FINDING bugs!

Otherwise this is shaping up to be a solid build and a good base to build on for our little phone!