Yes, it's out. I've been running it for over a week. It works great. You get Cydia for the installer for unofficial apps and then Apple's AppStore for the official apps. Both seem to work well with each other. I haven't seen anything really bad about the 2.0 firmware that I don't see AT&T (non-hacked) customers saying. It's definitely flakier than the 1.1.4 firmware, but there's plenty of new features too.
One thing worth mentioning is that the Cydia installer doesn't have much in it. Firmware 2.0 "broke" all of the 3rd party apps and most of them just switched over to the new AppStore. And those that haven't, haven't released much on Cydia's installer. So if you like Fring, or Devicescape Connect, ApolloIM, or any other app that pretty much violates Apple's SDK rules because it runs in the background... well, they won't be in the installer for a while... if ever. And if you really want Fring (for Skype), then I wouldn't advise upgrading at all.
http://www.winpwn.com - grab version 2.5