I've got Fedora running on dell, toshiba, compaq, and HP all without problems. Historically the pain points were graphics cards and wireless, but over the past several years vendors have become more open and I've gotten to the point where I feel comfortable picking up whatever is for sale. The two really big wins over the past few years have been the opening of broadcom wireless drivers and better open nvidia drivers.

how is dell burning you? I seem to recall at some point needing to pull down an extra kernel driver from rpmfusion for a wireless chipset dell was using but other wise ( and more recently ) my dell laptops have been pretty friendly.