It took what for most Nexus One owners seemed to be a lifetime, but we now have the download location for Android 2.2 (Froyo). Here's what you need to do to flash it to your phone:

Update: Yeah. Hang on a sec guys. Sorry bout that.

We're doing ours right now, so stand buy, and sound of if you're having fun.

Update #2: You can install a FroYo nandroid backup (courtesy of scepterr at the CM irc channel) as long as you're running ERE27

  1. Backup everything via nandroid (this isn't a rooted ROM)
  2. download ERE27 Here
  3. download the nandroid version of FroYo Here
  4. reboot into custom recovery
  5. wipe all data
  6. flash the ERE27 file from step 2
  7. When finished, preform a nandroid restore using the nandroid image you downloaded in step 3
  8. reboot
  9. enjoy some FroYo