Tempted to get one myself and retire the desktop
Noooo Mike.. easy boy.
Alienware have much improved service and warranty now dell are involved, quality remains the same (not quite as good as you expect but good none the less). Unfortunately they are still hideously expensive when compared to laptops like the MSI above and Asus G51 which do most of the bangs for a lot less bucks.
Asus offerings here
http://www.asuslaptop.co.uk/products.php?cat=70
G60 with the i7 quad sounds good to me, (I think that is what I am calling an G51 based on specs). It's a dual HDD laptop so lots of storage and speed (cant remember if they are in RAID but I imagine they are. The graphics cards are pretty much the same performance wise
afaik.
You lose the nice resolution though, back to 720p basically.