Is it too late to join the party? Hey, I'm Nelson!
Anyway, this is the long and short of it on creatine.
I'm not thrilled with it, but I don't think it's a scam. In other words, it isn't inert and it's reletively safe, so whay not....give it a shot. It works especially well on first timers.
The majority of it's effectiveness doesn't come so much from the ATP but from the water retention, which acts as a "hydrolic effect" on the joints. The thing with ATP is, it's like most nutrients -- you'll use what your body can absorb, and discard the rest. And the body can only absorb so much. Adding more will not add more strength. In fact, it's doubtful that you can absorb more ATP in a 24 hour period than is present in a hamburger.
The whole "loading phase" promo on creatine was concocted by James Bradshaw when he worked for MM2K. It was a total sales pitch -- absolutely no science behind it whatsoever.
I don't use creatine anymore because it smooths me out. But if you're on a bulking program, it isn't a bad idea to add it in -- especially since it's pretty cheap these days.