What's so great about Prince of Tennis!?!?

Okay, I seriously don't understand what is so great about the show Prince of Tennis! The show is purely based on tennis! What, is the most suspense it can muster is "Oh, no, he is going to hit me with his 'Flaming Deamon of Death' serve!" Seriously, it's just about tennis! What could POSSIBLY make it SO interesting that everyone is absolutely head over heals for it!