Mac versu PC,{snicker,snicker}

[Slick Fork]

If portability is not a factor for you I would absolutely hands-down go with a PC desk top for a couple of reasons:
1) You pay a fair sized premium for the portability of a laptop and could get a much higher end desktop for the same money
2) Upgradeability. You can upgrade almost everything in a desktop machine thus extending the useful life of the same basic system and spreading the cost of upgrades out over a longer time.

And the clutter isn't really that much more significant over a laptop, especially if you're plugging a mouse, keyboard, bamboo pad, monitor, printer, etc. in.