Magnum, I'm pretty sure there're some guys here running it. Provided you have a decent processor, sufficient memory and adequate disk space, I think you'll find that the platform (desktop, mini-tower, notebook, etc.) does not have an impact on the application's performance.
I use a Gateway notebook as my primary computer (Pentium 4 running at 2.2 GHz, 512 MB ram, 40 gig disk) and plan to add Autocad LT in the months ahead.
As far as brands go, I'm hearing good things about Dell and HP. My Gateway has run flawlessly, almost 24 x 7, since I bought it in Oct. '03. The battery went bad at about 12 months and began causing problems that took me a while to figure out; but once I replaced it the problems stopped.
What are you thinking about buying? I've been playing with the idea of buying a new notebook myself.