Nothing in the beta could have let us foresee that the iOS 5 update process would be harder than usual, but it was. It is fair to assume that unresponsive servers and possibly some issues with iTunes itself may be the cause of the troubles that some users have been experiencing today. At the moment, I suspect that the update Error 3200 is one that is related to unresponsive servers because after trying again, it eventually went away.
However, we have experienced a very long backup process that ended up as a failure. To expedite the process, we deleted a bunch of videos and moved photos to a computer. That took care of the problem. If you want to keep all your files, the backup may take hours, and it may fail. This is possibly an iTunes issue, we’re not sure.Some folks have reported that the upgrade file download took a very long time. Fortunately, this is one issue that we did not bump into, but it may just be that the first wave of upgrade has already receded.
Once upgraded, we had no issues to use iCloud, although you may experience two problems: 1/some have reported having trouble creating a new Apple ID 2/ to enable notes for iCloud and possibly other apps, you need a .me Apple ID. If you have been a long time Apple user, you probably have an Apple ID based on another domain. From what we can tell, it is possible to use different Apple IDs for iTunes and iCloud, but please take a minute to think it through as this may be disorienting.
Finally, some users have reported that the upgrade process has deleted files from their devices, and that is a big deal. In the past, we have seen upgrades leave messy folders, but this time it has been reported that playlists and books got nuked in the process.
Things should get better overtime, but if you don’t care about getting the upgrade “right now”, it may save you some trouble to wait a few days. Good luck. If you want unofficial tethering, a Jailbreak may help, but do it at your own risk (!)