Marshall was on the LA Weekly music blog and it locked up Safari. Leo says being on a Mac, it's unlikely to be a browser hijack. Marshall says he can't even reset it, though. So he force quit and went back to the site and it's still the same. This was probably trying to install a Windows program on his Mac, because these attacks don't target Macs.
The chatroom is saying to hold down Shift while opening Safari. That will keep it from opening the previous session, which had the site that was causing him problems. He should still reset his Safari browser from the menu, though.