Tae Bo is a great workout, I need to dust off my old tapes now that you bring it up!
I would, though, highly suggest folks take a class or two from a Martial Arts teacher (or sign up ) to learn the basic techniques. I took an aerobics class in college (needed the last hour credit, besides, aerobics + college ladies....do the math), and we ended up doing Tae Bo for half the year, and I spent half my time in the class teaching proper technique. Yeah, he goes over it in the warmup segment, but if there's no one there watching and seeing you do something wrong, you'll never know til you have an injury.
After Monday and Tuesday, even the rest of the week goes W T F