Are you asking if there is a maximum level? It sounded me more like you were asking if there is a maximum number of XP needed to level up to which I can say at levels in the 200s its a cycle where I might need X to get a level, then Y and then Z... then once I make that level it goes back down to X and then Y again and then Z... then back down to X I haven't paid attention in a few days but I do think it is a 3 tiered cycle.
Wow... I have only been playing since I discovered MyVegas in early January and am sitting at level 50. At least our Vegas trip isn't until December but level 1200 just sounds insane!