Umm Desktops are better for gaming! They are more powerful... and easily updated. Laptops still need to be plugged into the mains to compete with PC gaming, so you might aswell just bloody have a PC. Running on batteries shifts laptops into 50% power usage and shuts down all the good bits!

Sure, I brought my brother an alienware area51 with Geforce6800 Ultra about 8 months ago and its nice, yeah defo nice... but its massive, you can't put it on your lap and it lasts 25 minutes on battery!... You need to use a mouse to play games, because the touchpad is naff... and tbh its only saving grace is the nice TFT screen.