A damp terry towel with water, diluted vinegar, and most natural glass/plastic cleaners are fine. Microfiber towels can be nice in that they leave no fiber res, and they remove fingerprint oils easily. I use an automotive cleaner which is natural and ammonia free. I would avoid using ammonia given it has been shown to have some odd effects on some plastic and glass over time. I'd avoid any strong cleaner unless you have to. About 3-7 times a week, I take a terry towel and dampen it with water and a little of the cleaner, wipe the whole computer down, then polish the screen with a lint-free microfiber cloth.
I want to stress, however, that when I say DAMP, I mean using very, very little liquid. If you get any towel too wet, you can have the issue of water damaging the computer so you MUST be very, very sparing when using any sort of liquid to clean the MBP (or any electronics for that matter). The amount of liquid I use is best summed as: think of how much water it takes to make a cloth wet but incapable of being rung out and divide that by, oh, say ten.