There’s something afoot and it involves missing prims! Inara Pey has reported the issue in her update on Interest List and object caching but the problem seems to be spreading and the location of choice to spot the missing prims appears to be Tempura Island, as exemplified in a thread on the forums.
Basically what happens is that some prims aren’t rendering, you’ll see something like this:
If you look closely there’s a girl hanging in the air where there should be a prim, well the prim is there, hence why she looks like she’s floating, she’s not. Now if you look even more closely there’s a Linden in the foreground trying to figure out what’s going on, you get bonus points for spotting a Linden in the wild these days.