I'm just as confused now as i was earlier!
I don't specifically need a portable but surely it's more versatile?
I wouldn't mind trading some screen size for its features but it would either have to have decent storage or my 80Gig iPod would be a bit pointless!
Hello!

First of all, now when I've got a MacBook for my birthday

and still have my 17" iMac, I can say, that the extra storage of the iMac is very great, and the screen on a MB is just too small, especially, if its your only machine. Its fine on the go, but when at the desk, I'd like something bigger.
Second, it doesnt feel safe enough, if the only computer you have is laptop. Maybe its because i've had a lot desktops and no laptops

?
Also, if you dont really need protability, their no need for a laptop. Some people may get laptops instead of desktops because it can "save desk space", etc, but in reality, laptop takes even more space than the iMac or Mac mini does (surely less than a Mac Pro)
If you dont need portability, but think it'll be nice to have, after a couple of going outs with you MB, you'll use it more and more on your desk, so the "portable" part becomes useless