Going from jailbroken 2.2.1 to 3.0 i've lost the following features:
- Video Recording
- GPS turn-by-turn navigation
- MMS (yes, it doesn't appear to work with 3 sims - works with my optus sim)
- Heaps of awesome jailbroken apps and the ability to download more

I've gained:
- search
- landscape sms

I already had most of the other features like voice memos etc.
I can't express how happy I am with this hahaha. Now I'll have to mess around jailbreaking this one