I disagree with the notion that Ralston has been sucking up media attention. To the contrary, he has given very few TV interviews (the Today Show and Letterman) and all of the recent articles in outdoor magazines about him have not included original interviews.
If anything, he has kept a low profile, when he could have capitalized enormously during the feeding frenzy that grew during his hospitilization.
Also, who wouldn't appear on Letterman given the chance? I sure as hell would.