Update: 2.0 for iPod touch now officially released. You can purchase now for $9.95... er, when the link starts working. [warning: iTunes link]
Update 2: iPhone 2.0 now official as well. Looks like it's the same 5A347 build we all grabbed yesterday with a filename of iPhone1,1_2.0_5A347_Restore.ipsw -- the 1,1 looks new, though, so perhaps this version is a bit less cranky. Stay tuned.
Update 3: And, it's gone again. Now iTunes is telling us that our 1.1.4 version is "the current version." Fun!
Update 4: Well what do you know. 2.0 for iPhone is back up via iTunes. Is this a rollercoaster or what?
Update 5: Looks like the activation servers are on the fritz, so if you updated your iPhone you can't activate it with 2.0 just yet, leaving you with a locked iPhone. Even more fun!
Update 6: At least for us, activation is back up and running after iTunes sat in limbo for a good 30 minutes. So be patient, people. Looks like iTunes activation is working but is taking quite some time.
[Thanks, Gerald D., Victoria R., and Sangadang]