I think we're gonna see 2.2 a lot sooner than you think. The press got the update already on Nexus One's (earlier than expected) and according to Google the next phones to get it are the Evo on Sprint and DInc on Verizon. We just need HTC to make the Sense UI compatible. I cant wait to see them make my DInc run faster, if it gets any faster it might just vanish into fat air!
I agree, the media has had copies of 2.2 software running on N1 phones for a few weeks now. It's easy to assume if these writers have been playing with it, major hardware partners (Read HTC and Motorola) have had access to the code for even longer. The only difference now is that now the code has gone "Gold" and they can make their changes to the final product. I would think HTC will roll out OTA update in 4-6 weeks. I don't believe that verizon will hold up the update as much as people believe. Verzion has been moving away from the "Control" that they used to have on the UI we used to see. I'm sure the major things verizon will check for are Stability, call quality, and wireless tethering.
Not really sure why everyone is rushing this, if HTC rush's this everyone is just going to complain how it doesn't run right, crash's yada yada yada. I would rather wait for a polished product rather than a Sense UI that doesn't take advantage of the new compiler.

And the fact the Tmo 3G coverage is weak anyways.