I think you will find that for the most part, the majority of Celtics fan would grudgingly agree that Kobe is better than Pierce (despite how much many of us hate Kobe in general).
I think it is tough to take a lot of what Pierce says seriously anyways, because he is the type of guy who is constantly joking around, and often has his tongue, firmly planted in his cheek. In this case, I think he may have been serious, but I certainly don't think he was trying to degrade anyone...he just is a confident player.
So yeah, I completely agree that Kobe is the better player than Pierce. Kobe is probably the best player in the league other than Lebron (and thats even debatable)...but I still would take Pierce over Kobe 10 times out of 10 as a fan, because he is so much more likable IMO.