I've been comparison shopping lately and I can't find a $999 laptop that has a screen less than 15 inches, battery life that's greater than 2-1/2 hours, GPU that's decent (the 9400m is the best integrated graphics card on the market), and isn't from a completely unreliable company. Most computer companies will offer large HDD, lots of (slow clocked) RAM, a beastly CPU, and a crappy integrated Intel GPU. I don't own a Mac but I've been shopping around for about half a year now trying to decide when to buy a laptop and have yet to find anything that's better than the white macbook for $1000. There are some "desktop replacement" laptops in this range that will outperform the macbook, but they weigh >8lbs and have a 2 hour battery life, not to mention the discrete graphics will most likely cause overheating issues if you dont keep it propped up off the desk (or your lap).
I was thinking the white macbook was crap, but after the recent upgrade to DDR2 800 RAM, giving more breathing room on the base HDD, upping the CPU a tad (not to mention already having a P-series core 2 duo with 1066MHz FSB), and increasing the expected battery life by half an hour, the white macbook is certainly competitively priced with anything Dell or HP has to offer in this range. Of course Toshiba and Acer will have cheaper stuff but from what I've seen you get what you pay for with those companies. Don't forget to compare it to over sub-14inch laptops since laptops get more expensive as they get smaller.
And don't bother bringing up the Dell XPS m1330. The slower RAM, less efficient CPU and terrible intel x3100 graphics chip should be an embarrassment for the company's gaming line. I use to think the decision between PC and Mac was black and white, but now that I've compared what all the main companies have to offer I see that the difference in performance is very little if you catch them at the right moment.
Oh, and if you game a lot then you should have a PC desktop. People who say Macbooks are terrible for gaming are correct, but laptops shouldn't be considered as a primary gaming system.
Sorry if I sound bitter or angry because I'm not trying to be :/