I definately prefer my desktop performance & reliability wise, but the laptop is portable.
It really depends on what you do with them, I can't throw my desktop in the truck & take it with when I need it.
If you just surf the internet, check your email, & download a couple of files every now & then a laptop is fine, & comes in handy if you need something portable for work. Massive downloading, burning, games & graphics are much better handled with a desktop IMO.