public release very soon.
iOS 4.2 GM was released to developers a few days ago, and no one reported any major bugs or issues. The only known issue is that you have to run the latest iTunes ( which is currently in beta – and might be released today ) in order to activate your iPhone.
We already talked about the upcoming update of Cydia, but we also want to remind you to make sure you have your SHSH blobs saved. Anyone with blobs for iOS 4.1 or earlier should be able to get an untethered 4.2 jailbreak.
To save your SHSH blobs, you can use TinyUmbrella. If you don’t know how to use it, check out this tutorial. ( the UI was redesigned, but everybody should be able to figure it out )