Maybe this'll light the fire under Google's asses to hurry and release it OTA. I'm starting to grow tired of waiting to get it on my Nexus One without downloading the leaked ROM and rooting my device, which I'd really rather not do.
You don't need to root your device to install the unofficial Froyo image. It's still an image signed by Google, so you can use the standard bootloader and flasher on your N1 to install it from the SD card.
I did this with mine and my wife's N1, and neither one has an unlocked bootloader, and neither one has rooted firmware.
Dunno about the other chap, however I own an "AT&T" EPE54b image device, and for us the only option is to root, roll-back to a incompatible image, and then roll forward to Froyo.
Easy enough, but this phone is an important communications device for me and I don't want to mess around with betas. It's just surprising that Google has mangled this release so badly.
Sounds like your devices are not being controlled by Google, but are instead being left in AT&T's hands... I'm very sorry to hear that, but it shows yet again that AT&T is the weakest link...
AT&T has nothing to do with the "AT&T" N1, and 2.2 is not officially out for any N1 model, be it the T-Mobile version or AT&T/Rogers version.
The devices getting the Froyo update via OTA right now are a subset of the AWS-compatible phones that Google first released in January, and handed out to the press and Google employees. In other words, there's no Froyo update for the N1 made for the AT&T/Rogers bands because Google's not using them to dogfood the OS image right now.
edit: now if we get into how there are some apps you can't get on the Android Market because AT&T told Google you can't have them, that's something slimy that AT&T is doing. For example, if there's an AT&T SIM in your phone, the Market won't let you download PDANet. Pull the sim, though, and there it is...