I've been friended by two three different Russian accounts, neither of whom I've ever heard of and both of whom type solely in Cyrillic.
If anyone else is having this issue - although you can't stop an account from friending you, you can report a suspected bot using this form:
http://www.livejournal.com/abuse/bots.bml And you can ban suspected bots from posting on your journal by entering usernames here:
http://www.livejournal.com/manage/banusers.bml I can't wait to see how many more "friends" I end up collecting... :-/
ETA: The pattern I've seen in the bots so far is an origin date of 2009-09-08 at around 15:00 or later, for whatever that's worth in tracking.
Also, the eternally-awesome
draycevixen showed me an LJ feature I apparently deactivated, which gives one a popup with the above capabilities when one hovers over a userpic:
http://www.livejournal.com/support/faqbrowse.bml?faqid=301