Well... I just don't HAVE a lot to tell you.
We have been unable to replicate it. It's been reported on iphone 4 running the current IOS, which I have... and I see the site perfectly normally when I come here.
It's hard to fix a problem if you can't see it.
Clearing your safari cache & cookies apparently will not resolve it.
Otherwise there doesn't seem to be an apparent link between those who are experiencing this issue.
Is anyone using the iphone skin? Or Facebook Connect? I'm at a loss.
Paul