Which developers? Whilst Diablo's been out we've had Tear, FlipClock, and many others. But you're right; Diablo's been a maintenance release so the flurry of stuff for Chinook's carried through to Diablo.
As for Fremantle, external developers are already doing cool things and are excited about the increased CPU power, 3D acceleration, accelerometers and more compelling UI.
If you're talking about Nokia developers, I don't see your point.