The news of Mariotti's resignation is a day or two old, but I didn't read beyond the headline until now. Interesting that the web is the reason for his resignation.

Jay Mariotti, the opinionated and polarizing sports columnist for the Chicago Sun-Times, has resigned after 17 years with the paper, he told the Tribune on Tuesday night.

Just back from Beijing, where he covered the Olympics, Mariotti said in a phone interview that he decided to quit after it became clear while in China that sports journalism had become "entirely a Web site business. There were not many newspapers there." He added that most of the journalists covering the Games were "there writing for Web sites."

Mariotti, whose public battles with fellow staffers, team owners, managers, coaches and rival columnists are legendary, didn't disclose any specific plans except to say he will continue doing his regular stint on ESPN's "Around the Horn."

He said he "is talking with a lot of Web sites" and added that the future of his business "sadly is not in newspapers."
 

http://www.chicagotribune.com/sports/chi-27-mariotti-jayaug27,0,609457.story

This is my favorite explanation:

According to two reliable sources, Mariotti, just back from Beijing, wanted to write a column on Barack Obama. But it wasn't Jay's turn to write — it was Rick Telander's — and Telander also wanted to write on Obama. And we know how Mariotti feels about Rick. Sun-Times says no, Jay, wait your turn.

Here's Telander's column.

And so Mariotti, showing the maturity he's famous for, calmly assessed the situation and figured he was not going to let it bother him. Just kidding! He threw a fit worthy of a three-year-old. Then this bit of greatness: Mariotti resigned, and then headed to the Sun-Times office to tape his Around the Horn segment, only to find that his security pass had been deactivated while the paper was deciding whether or not to accept the resignation.