I can't decide if the messaging is worse or just different. Either way I knew it would take some getting used to. Same with the virtual keyboard, gonna take some practice.
One thing I miss already is the ability to make custome ring profiles. Like "Phone only" on the BB turns off all notifications except the phone. I used that profile at night so incoming emails wouldn't wake me up but the phone would still ring if I got an emergency call. As far as I can tell the EVO just has Normal, Vibrate and Silent.
Still, the EVO is a far, far better multimedia device. I doubt I'll ever go back to BB (or any other non-android device).
Not sure about FB but for yahoo go to Mail > Menu > More > Settings > Send & Receive > Set Download Frequency. Set your peak start/end time to a 24 hour range and then set the Peak Frequency to 5 minutes. Not quite BB push but pretty good.