I'm the exact opposite. I used custom built Linux desktops for years. Switched to a Linux laptop and never looked back.
Sony Vaio F12: quad core, 8GB, SSD, 23" LG travel monitor (5.5 lbs, nice!), iRizer laptop stand. Cost: 1/2 MBP. Code warrior: I be
The only thing I miss from OSX is Finder; well, the window manager as well; let's not forget the spinning beach ball either ;-) People, Linux is a gift from above. OSX is great for consumers, and is de facto the best OS on the planet, but Linux is the best OS in the universe -- big difference...