Well of course desktops are better everyone. If a laptop was that big I'd expect just as much. But the amazing thing is now Laptops are coming with hardware that can easily compete with desktops. For the most part, you can get the same hardware that you get in a desktop, in a laptop. The HDs are much bigger with desktops now though, but then there is the wonder of the portable hard drive(usb).
My vote went for the laptop because of the fact that it is like a desktop, only portable. Even on my crappy acer I can do almost anything I can do on my desktop(which is probably one of the better single core PCs still around(but in some ways better than those dual-cores since it lacks Vista, which takes up a core and half your RAM
)).
So I guess if you are looking for full blown power and performance(like quad-core with 768 MB after market graphics card), then go with desktop here. It does suck that laptops don't have PCI ports or anything, so you are stuck with most of the default hardware parts, but I have no complaints really. My laptop does everything I need it to do, but I can do this anywhere(and I move around(yes outside of my house!) alot) so it is very nice to be able to enjoy games, music, movies, the internet, and work on documents and projects while being virtually anywhere.
But I will make an interesting statement. Desktops are getting smaller, much smaller. While not 100% portable(yet), desktops are getting small enough to get noticed for such a thing. If they could just make a wireless moniter PCs then make a battery connection on a PC, PCs could be rather portable(wireless keyboard, mouse, network card, moniter, then hook up your battery and you've got desktop power computing anywhere). That actually is a great idea with the way things are going(PC size and wireless capabilities).