I'm finishing up my fifth year of engineering (this past year has been for my masters). For my undergrad I only had a desktop pc and it served me well. This past summer I bought a MBP; i never used a laptop as my main computer, especially a mac, but the fact that i could put windows on it pretty much sealed the deal. I rarely use bootcamp (i don't use parallels; everything i need to use in windows won't work in parallels, i.e. flight sim, Inventor (CAD), etc), but when I do everything i need (engineering wise, and other) works perfectly. As a matter of fact, as I noticed while running a huge matlab code recently, matlab does run about 60% faster on windows than on os x, but it's common knowledge that it's not optimized for os x. All of my engineering work, for the most part, is either in matlab or excel and 95% of the time i'll get done what i neeed to in os x.
That said, I'm not sure what your budget is, but i think that a macbook would definitely be able to do what i do with my MBP. I know a few people that have gotten by the past few years (in engineering) with ibook's so that would not be a problem. I absolutely love my MBP, and the screen real estate (17") really comes in handy when doing work. Also, a lot of your work might also be done in computer labs with machines that have the specific software you'll need on them, so your personal computer need not be the greatest, most expensive and fastest machine. Good luck with your decision!!!