We've just had one of our 7650's updated to firmware 4.39 and it looks like a whole load of the J2ME function now doesn't work correctly!
For a start, drawing with clipping to an Image (offscreen Graphics context) seems not to work as expected any more, with the clipping being ignored.
There seems to be some lovely new transparency issues with both pngs and the UI. I've not had time to investigate further yet.
Several of our games now crash when accessing the record store, although not all the time!
One of our more faster moving games, which was working fine with full screen multi direction scrolling is now really jerky. Not just in game too, even the menus (which slide in and out of the screen) are no longer smooth.
It's great isn't it? You spend 2 months getting a great game up and running, only to have it fall around your ears due to a firmware update, which is supposed to fix things.