NSLog();

Safari usage has skyrocketed across the Web. Have a look at John Gruber's statistics, and then compare them to mine (I've pared mine down to just the Mac clients).

The past 24 hours:

Navigator/Mozilla               22
Omn                             82
Chimera                        234
Safari                         969

The numbers speak for themselves, I guess. Perhaps tabs really aren't that important. What is interesting, however, is that not a single person using IE for the Mac visited my site during that time frame.