My opinion is this:
Gaming == desktops
Portability == laptops
Don't buy a laptop and expect it to play games on full res + all settings on max.
Laptops are extremely expensive for what you get, and the quality is lower. You can buy a desktop that will be SUBSTANTIALLY BETTER than a laptop, for A LOT CHEAPER.
Also: Every single person I know of, that has bought a gaming laptop (5+ people, ranging from alienware to asus to dell) has had overheating problems.
Conclusion:
If you want power, go desktop; it's cheaper, and more powerful.
If you want mediocre battery time, heating issues, and portability; go "gaming" laptop.
If you want what a laptop SHOULD be used for, get one with a 15 inch screen, an i5, 4gb of ram, and make sure it has good battery life.
Now, I'm not saying laptops are bad, on the contrary, they're great, just not for gaming. If you are going to get a laptop, I recommend an Ultrabook (from notebook to netbook to ultrabook). Or a "regular" notebook, with "medium" specs, so it doesn't overheat.
My experience:
Gaming laptop, lots of friends with them.
A netbook
Built my own gaming desktop for under $700
I'm also pursuing a computer engineering degree
