A laptop is compact and convenient while some options seen for laptops now are better then seen in previous years. I considered getting a laptop here all often but mainly decide on what I want in a desktop. There you decide what goes into a custom build over having only this or that as an option for most laptops and prebuilt desktop models.
Depending on "who" makes the laptop is another concern. Some like Sony, Vaios some don't; some like Toshiba, some don't; some like Dell, ??????? that's how that goes.
The make and model however determines the options like a better addon video card if the option is there over the onboard is a thought for a gamer. Addon sound over onboard is less likely since while traveling headphones come into play often.
Portability and still being able to use a mouse and even an external keyboard and monitor is one thought. Touch pads on notebooks/laprops? Sorry give me the optical trackball mouse or even a standard 2 or 3 button. That's the drawback when on the road and trying to game there if you sitting with a portable in your lap and not on a flat surface like a table or desk.