If you're a gamer on the go, and you aren't a hardcore PC gamer that needs to upgrade their system once a week to stay on the bleeding edge, then you'll do fine with a laptop, all you have to do is remember the things that are fundamental to laptops;
they're more expensive, so a larger down payment for the same reward
they're difficult to upgrade, so you'll want to get the most powerful one you can if you want to keep uptodate gaming on it for more then a couple years
Everything else is just a thing - the keyboard is fine once you get used to it - every keyboard that's different from the one you use all the time feels weird, it's just part of using the PC, and with a USB mouse, you don't have to worry about the touchpad or *ugh* nipple mice unless you're actually on the go, in which case, gaming on a PC isn't really that great when compared to PSP/DS opportunities.
Don't get scared away by people that say it can't be done or it shouldn't be done, just keep those 2 points in mind, and you'll do fine.
