I'm looking to get a laptop in August to take to university. While I'm not particularly much of a PC gamer, I do play some games on my PC (Final Fantasy XI, Phantasy Star Online: Blue Burst, Unreal Tournament 1/2k4/3 etc). For this reason, I dual-boot Windows, but the dream is to one day stop that. But it means I do need reasonable graphical capabilities.
I also prefer smaller laptops. 17" is far too big, 15.4" is okay, but those 13" ones are damn appealing.
Surprisingly, Dell seem to do some really nice looking machines.
The main difference between the two machines is that the 15.4" has an 8600M GT w/ 256MB and Blu-Ray, whereas the 13" has 8400M GT 128MB and no Blu-Ray. Blu-Ray is appealing, but it'll be a while before it's really feasible in Linux. The main factor is the different in GPU - how much do these really differ in terms of power? I'd love to go 13". Gaming isn't going to be a priority in university, but I don't want to cut myself off from games entirely. Mainly the ability to use UT3 and the forthcoming Fallout 3 would be nice.