My experience with Visual Studio 2008 was vastly improved when I went from a mechanical hard drive to an SSD. Times to load the IDE and to find help information were drastically reduced. If you're going to use VS then I'd highly recommend an SSD in your laptop.
well, i just bought a Compal NBLB2 with Core i7-720QM + 8GB ram (multiple VM's at the same time) check my configurations for more specs
more than likely you probably don't need that power, a simple Dell/HP/take your pick brand will work just fine
EDIT: there are quite a few students who use netbooks and they do the job fine, unless you are doing computational heavy tasks which you won't be since Software Engineering is more about developing apps as opposed to the Computer Science which is about theory and computation (actually trying to minimize the amount of steps to reach an answer)