I was trying to figure out what to do (besides report it).
Logging out and back in didn't seem to have an effect, so I tried changing my password, just in case. I don't know if that had anything to do with it, but now my profile is back...although at last check my bookshelf was showing *no* books. (If putting my profile back is the work of someone behind the scenes, THANK YOU!)
However, if I put in the URL for a book I know should be on there, it comes up as registered by me. So I know I'm still in the system...
I'm not obsessive about the stats, but it's a bit upsetting to see no books on my shelf. I hope it can be fixed... :(