Automatic Trans problem?

Just noticed today that my car started to lack power, its a 2005 TL Auto, the engine it self is perfectly fine, but once a load is on it, it feels like it just doesn't go any more, just wondering if anyone else had a problem w/ their trans...its got a warranty so ill just drop it off this weekend....

I know the 2000 to 2003's had lots of problems but I haven heard much out of the new gen. You should be under warranty still.