I just read an article from SlashDot.org that got me wondering.  They are reporting about 70% of users are using IE, about 15% FireFox, and about 5% Safari, with the rest too small to matter.  I looked into my logs of 3 sites I host, and they tell a completely different story.  All the data I am going to quote here is aggregate data since about October 06. 

Ircmaxell.com

1. FireFox  - 42,458 Visitors (70.29%)
2. IE            - 14,837 Visitors (24.56%)
3. Safari     -   1,319  Visitors (2.18%)

BagsOfCrap.com

1. FireFox  - 185,661 Visitors (59.86%)
2. IE            - 109,510 Visitors (35.31%)
3. Safari     -      7,980 Visitors (2.57%)

NBVFC.org

1. IE            - 9,329 (86.53%)
2. FireFox   - 1,226 (11.37%)
3. Safari      - 111 (1.03%)

Now, What's the reasoning behind this?  Ircmaxell.com is geared more towards power users (programmers, webmasters, etc) rather than every day computer users.  BagsOfCrap is geared more towards the power user, but includes a decent percentage of "regular" users.  NBVFC.org, on the other hand, is geared towards the every day person.  At the risk of sounding like an a$$, and starting a flame war, it almost seems like you can relate how much a user knows about computers by the browser (s)he uses.  Just an observation...