Wickedsight:
I've had a six month stress session over this same question: what Mac lappy to get for Serato, and Live?!!!!!
Six months because that's how long (I think...probably longer) that I've been aware of Nahalem based processors coming to MBP's. Now that they're out (and lack luster I must add) I've had the question of what configuration to go with. With the thought that I probably won't swap out for 3-5 years.
Background:
I've been mixing on Serato with a 1.5ghz 15" Powerbook since 2004. It has been bullet proof this entire time (I knew the day would come) until Serato came out with the SL3 interface. These boxes do not work well with PowerPC (Powerbook) processors. I encountered all kinds of screen glitches and program freezes when spinning through one (audio never dropped out

). This is mostly because the new interfaces rely more heavily on the computer to process sound. Being that these new boxes are ill (because they run audio at 24bit) I have to finally drop coin on a new lappy. Which brings me to....
Processor & Screen Size Choice:
The processor and screen size were a mostly easy choice. I was intending on a 13" i5 (i5 because its
PLENTY for playing out with either Live or Serato. Don't let
anyone tell you different. If you wanna produce, then get a proper DAW desktop set up), but Intel and Nvidia fuct that up. So no i5's for 13's (I wanted a 13" so i could cram it in a flight case if need be). So the choice was obvious: i5 15". That's fine cause I've been using a 15" for six years now with very little issue with portability. Next question: Glossy or Matte? Argh!!! I hate glossy, but I hate dropping loot on something that should be stock to begin with! Dropping $150 for a matte screen that I'd be fine with a 1440 x 900 resolution on is lame! Lame!!!! But I hate these glossy screens just as much (BTW, they don't look like Macs, kids. Glossies look like ghetto Toshiba's on discount at Costco. Its a new-er fad that I hope goes away quick!), so I have to come correct and get the hi res matte option. You're stuck with it for years, and if you spin outdoors at all you'll wish you had a matte screen. And as I said.....Toshiba's!
If you're still unsure about the screen then go to your Apple Store and load pages with screen shots of your intended programs of use, and then decide.
Also consider that when you're kickin' it on the couch digging for tracks, and you've got the MBP on your chest, that a glossy (heavier glass) screen will be flopping down on you under its own weight (real annoying!). Not conducive to comfort or efficiency. Same goes for laying in bed.
Another consideration:
Hard Drive. Just get the stock drive. You can get a better drive with a better warranty for half what Apple wants for the same capacity / spindle speed drive. Also, 4 gigs of RAM is all you'll need (currently) for audio. SSD's are unnecessary for your needs.
BTW, the Powerbook is still rock steady. I plan to use it for the harsher environment outdoor events until the logic board takes sh*t. I hope this next Mac is just as reliable!
Werd