Melsi, it seems clear that you were already set on a laptop and no advice from anyone will make you change your mind. It kind of makes me wonder what the point of the post was, but I guess it doesn't matter.
I currently use a laptop for all my recording. When I started using it, I thought portability was a big plus, but that's not really true. For it to be truly portable, I'd have to forego the use of not only my audio interface but also my studio monitors. So, what's the point of portability? If I'm looking to do field recording, I'll just buy
a Zoom H2 or something similar -- incredibly portable and gets the job done.
When I get ready to build a new DAW, it'll be a self-assembled rackmount case. Why?
1. It will fit in the same rack as other studio gear I'll no doubt be purchasing.
2. the rack itself will be a flight case. If I truly need to move my studio, I lock it up and with me come my DAW, interfaces, pres, etc. The only thing left to case up is my monitors.
3. Ease of upgradeability/repair. Sure, laptops can be repaired, but I don't have tiny robot fingers... why would I force myself to work in such a restrictive environment?
4. A good quality rackmount case should last for many, many years. Even if technology has a grand explosion, worst-case scenario, I'm slapping in a new mobo/cpu. Not the case with a laptop -- it's replacement time regardless of whether the internal hard drive, display, etc. still work.
5. NOISE CONTROL. Throw a blanket over that laptop for 30 minutes while you track and then do it again tomorrow. Pray that it doesn't overheat. Laptop fans are loud, bottom line. I can keep my rack in a control room with a monitor, keyboard, and mouse in the tracking room AND the same in the control room. This can also be done with a laptop but what's the point -- you've just negated the portability aspect.
6. I may get hassled on this one but it still seems from my research over the past year that the best interfaces/DSPs/etc. are PCI. While I don't doubt this will change as more designers lock onto FireWire, I'd rather have both options at my disposal.
That's a newb's take. I bet you'll still go for a laptop, but at least consider the advice you've been given.