I don't follow the PC wars much, but supposedly Dell's been declining in quality in the past few years. I suspect their expansion into the low-end market has hurt their geek cred.
I have a still-reliable P-100 Gateway from back when Gateway was on top, and I never quite trust my HP bought in 2002.
I am using a five-year-old Dell Laptop right now, still works great except it can't handle internet video very well.