I have been having trouble with iTunes as well. I can understand the store being down due to high volume and Christmas sales, but my iTunes software problems (unrelated to the store) have been ridiculous. I have an iPod mini and have used it with no issues for a couple years, but I got a new iPod video for Christmas today and suddenly iTunes started freezing when I tried to sync it. The first time I set it up it worked fine but then all **** broke loose.
First, I uninstalled version 7.01.16 or whatever (the newest one) and installed version 6.05, but discovered that it wouldn't work with my new iPod. So don't try that. Older generation iPods can try it, though. Here's the link for old applications of iTunes:
http://www.oldapps.com/itunes.htm
What ended up finally working for me was uninstalling the new version, reinstalling it, and restoring my new iPod. I disabled automatic syncing of photos AND of music. So now I have to manually install anything I put on the iPod but frankly as long as iTunes doesn't freeze every time I connect my iPod I don't care. I assume reinstallation won't be necessary but I did it anyway. The key is to do the restore before iTunes freezes, which was in about 15-20 seconds for me. It might be shorter for others so I recommend doing it ASAP.
I am hopeful (ha!) that soon the issue will get cleared up and I can switch back to automatic uploading of my iPod. For the time being, however, it works manually and I'm happy.
Good luck to everyone. It has been a frustrating day for me but I hope I have helped someone who's been as frustrated as me.