I had a blackberry curve 8330 for just under 2 years and moved to the shift almost a week ago.
Stuff I miss from the BlackBerry:
1. The keyboard (im sure ill get used to this one, but the placement of the keys was easier)
2. The ease of mail setup (auto in most cases)
3. Blackberry Messenger (not so much as everyone went to other devices or found other means to communicate and was pretty much phased out anyways)
4. The ease of setting custom tones and navigating files
5. Auto converting messages longer than 160 characters from SMS to MMS (I know a lot of people are just the opposite, but its kind of annoying when reading through 6 pages of a horoscope and getting cut off)
What I don't miss:
1. The battery pulls
2. The blank messages
3. The ever sticking trackball (cleaned and replaced several times)
4. The update to the desktop manager which no longer allowed app backup (had to restore to factory and repurchase and redownload quite a few things)
5. 3g only

6. The 7-10 minute boot up
Here's what I like about the Shift:
1. Android
2. Touchscreen AND keyboard!
3. Much faster (freezes a bit but ill figure that out)
4. No more battery pulls (knock on wood)
5. Great voice quality (better than my BB IMO, but speakerphone could be louder)
6. Angry Birds!!
7. Great Community
8. Market is much easier and faster to navigate than the BB App World
9. Perfect size (almost wanted EVO because it was bigger, but came to my senses)
10. Picture quality is amazing
11. So many options
12. I may edit as i find more things lol
What I dont like about the Shift:
1. Battery life; blah!
2. freezing (again, im sure ill figure that out even if i have to take it back)
3. keyboard character placement
4. lack of native call timer records
5. lack of FFC (wouldnt mind it so much if there was a hard button for the cam when taking self shots)
6. Battery Life!!!!!!
Overall I LOVE the Shift and can see me using it for a long time to come