Since I launched this thread, it is obvious that most people are seeing improved 3G service or no significant change. While my reduced 3G connectivity is certainly real, perhaps it is limited to my area (Louisville, KY) or to some issue peculiar to the software milieu in my phone. Shame, though. Big and noticeable change since 2.1 for me. Thanks for the responses.
Since 2.2 I've noticed worse signal strength. I'm in the Hudson Valley in NY (no 3g coverage) and now my Edge reception is worse. My phone spent most of yesterday "searching" for a signal when it'd normally have 4 or 5 bars. Eeep!
I've noticed that since 2.2, when I do lose any form of AT&T connection, it now takes forever SEARCHING to restore service. Usually, I find it quicker to power cycle the iPhone and grab service back. I'll probably attempt a restore this weekend.