As long as you don't completely cheap out, it'll be hard to find a laptop that won't be very good at what you're asking of it, because you're not asking too much. Since you're considering MacBooks, I'm assuming you have a budget of at least $1000.
I really love my MacBook but unless you're really leveraging Apple-only software, it's hard to justify the cost. That said, the new generation are very powerful machines, I just think anything more than a 13" would be overkill for you. You don't need a quad core.
My one universal piece of advice is to get a machine with Intel's Sandy Bridge chipset. All manufacturers are
just coming out with them now so there won't be a lot in retail stores but there will be much more in the next month or so. Sandy Bridge machines, in general, have a significant jump in performance from the previous-gen machines.
IMO the sexiest laptop available today is the Samsung 9 series:
There are a
lot of Acer haters on here, and for good reason, but the new Timeline series are very nice looking machines too. I've got a 2010 Timeline and I've had no issues with it whatsoever. Super light, 8+ hrs battery, iX CPU. More than enough for your needs. They're just about to release their Sandy Bridge Timelines.
