I saw an episode of MindFreak where CrissAngel was doing an underwater escape trick in NYC when Blaine came by to "show his support". This was very similar to Blaine's very similar to the David Blaine live-in-water-for-a-week/hold-your-breath-for-world-record trick he did in NYC. CrissAngel said that appreciated the gesture, but I think Blaine was pissed. I think that Blaine feels he's legitimate and than Angel is stealing his thunder. I tend to believe him.
I think the Blaine/CrissAngel thing is very similar to the rivalry from the Prestige. Society can only take so much magic, therefore there is a constant battle to be the "one magician".