All lights are green here.
No problems here (knock on wood). Updates on a MacBook (2009), MacBook Pro (2007), two Mac minis (2009, 2010) from SL to Lion.
Typically, I like clean installs. However, this being a new beast (no pun intended

), I thought I'd see if Apple really pulled it off. Besides making sure all software we use had been updated to support Lion, all available updates from Apple installed, and Disk Utility showed everything was copacetic prior to install, we didn't really do much else in our firm.
So far, users seem for the most part pleasantly surprised with some of the new features. However, there have been a few complaints here and there that things were missing or gone; typically, it turned out that Lion provided an easier method, just not immediately apparent. I left it to people to ultimately decide if they want the new scroll direction or the old but asked that they give the new way a try for a few days before reverting to the old. As some have reported on the Internet, we, too, noticed Safari and overall performance slow on the first day after install but finally being much peppier than even Snow Leopard by the second or third day at the latest.
If things go well over the next two weeks, I'll deploy it to the rest of our machines. To those having any serious issues, good luck and I hope they are resolved soon.