It's because of the Jacksonville market and the lack of success they've had over the past few years. Houston's a decently-sized market and gets their attention whether they're good or bad. Tennessee doesn't get much love on the networks because of their market, but CJ is recognized all the time because of his contributions to the 2008 13-3 year and obviously the sixth 2000-yard season in NFL history.
I think everyone on here recognizes how good MJD is. Casual fans don't realize or don't care about his production however because of the, for lack of a better word, irrelevancy that has surrounded the Jacksonville franchise lately.
And like everyone has said in here already, Pro Bowls are nothing anymore. Although I'm still a fan, that second-string quarterback for the Eagles has made two Pro Bowls when he hasn't ever been qualified to make one. Pro Bowl voting results are nothing to scoff at.