iPhone firware version 2.0.2 was released yesterday. I promptly installed and after having used it for a few hours now I can see the light (quite dim still) at the end of the long slow performance tunnel. Settings and Contacts visibly faster for me now. I have not yet had any random crashes. Fingers crossed that the devs over at Apple release a spiffy firmware with 2.1, which I hear is at beta 4 now.