You aren't looking for the IGP to tie up gigabytes of RAM. It's not a big deal in terms of usable memory space if you're only doing a couple of things at a time. If your maximum budget os $1599, then go for the 2.4 and upgrade later. factor Applecare in as well sometime during the 12 months of ownership - more than any other manufacturer I say you'll need it.
Be also aware of some caveats:
To get full performance of Windows you'll need to run Boot Camp - but, contrary to many opinions, that BC environment is not fully Windows compatible. The clearest example is the fact that Boot Camped environments will fail with some commercially copyright-protected engineering & design applications. There are also driver issues to be contended with - power management, video handling, sleep and hibernation are some issues you'll come across with Vista and a Boot Camp environment with a current Macbook. The overall environment is also less reliable than on a 'real' PC - although many people chalk that up to Windows predictably enough, I have to say the only Vista BSOD's I've seen over the last year is on Apples in Boot Camp.
My 17-inch unibody Macbook Pros - which, seeing as they are my newest Macs I Boot Camped with Vista - and they still fail the power management, sleep/hibernate cycle and also some low-level compatibility tests, as does the Macbook. It's not a panacea, and with real-life general application-use runtime of 3 hours 45 minutes for the Macbook in OS X power saving mode (I have the 2.4Ghz models) it's fine, but not a spectacular runtime for a current machine with an IGP. There are some which can manage this runtime even when equipped with the GPU in the same sort of low-impact tasks.
Put quite simply, with Apples there's a huge degree of smoke and mirrors you should factor in - both good and bad. The plus side is of course the sleekness of the machine. I have other price-comparable Windows machines including the Sony Z - hardware wise a much better machine than the Macbook - and lookswise, it's a no brainer. That plus the tactile aspects of aluminium make the machine nothing short of strokeworthy on the surface, but it comes with a number of failings which are disguised by expert marketing and a legion of mindlessly devoted when crowdsourcing opinions, which isn't a facet of other makers simply because they're absolutely no good at the marketing and Moonie-like fanboy quotient, try as they might.
A 2.5ghz Dell Studio XPS 13, loaded with significantly superior specs (4Gb, 500Gb HDD plus the usual amenities such as Bluetooth) as well as better hybrid SLI / CUDA support (the 9400M and the 9500M can be used together) as well as an extensible 2-year onsite support is the same price as the base 2.4 Macbook. I have it's larger sibling, the XPS 16 and I have to say the build quality on the XPS range has improved since the last generation - and these are solid machines. Personally if you're looking to do the heavier lifting in Windows, I'd plump for the Dell. It's heavier by about an iPod Classic, but it's a significantly more functional machine.
I'm having difficulties deciding what type of computer to buy for college and was considering running a vista dual boot on the new aluminum macbook to take advantage of both operating systems. Since I'm planning on majoring in engineering, I was concerned whether the integrated video chipset on the mac was powerful enough for running CAD programs and other 3D applications (such as light gaming). I was pleasantly surprised by the macs performance in some of the benchmarks/videos i've seen online, however, which raised my big question:
-If i would buy the new macbook which model would yield better 3D performance?
-the 2.0 ghz model with 4 gigs of RAM (since integrated video shares this memory)
-the 2.4 ghz model with 2 gigs of RAM.
Any input would be appreciated. Keeping in mind that I'm not looking to spend more than $1500... (which leaves the 2.4 ghz model with 4 gigs of RAM out of my price range)