I'm using 3.0 FW, and have installed SBSettings and a few RockYourPhone apps.

I've been having a few problems specifically with the stock Mail application.
When I press the button to compose a new message, the screen comes up with no keyboard and the buttons won't work (Cancel and the contact lookup). When I press on the message area, the cursor moves there and the keyboard comes up and everything works fine. There are also times when I exit the Mail app using the Home button and the keyboard is still on the screen. I have to respring (using SBSettings) in order to get the keyboard to go away.
I've also had issues where button presses don't work right in the Mail app. When I press an email to read it, it flashes but doesn't open. This happens quite often. Many times by pressing it slower a few times it finally works, but sometimes I have to exit and reenter.

Not sure if these are related to RYP apps, but I figured I'd post here to see if anyone else is seeing this issue.