A.G.
Being sore doesn't mean you are doing something right, its the bodies way of saying your muscles need rest. It is true though that we hit plateaus in our weight loss efforts. The body is designed to hoard fat, especially the female body. tricking it is the best way to go. Ive had a lot of trouble keeping my routines fresh and new, i have a lot of things that keep me from trying things (i have a 3 year old and no baby sitters(which limits a lot), Im pregnant(even more) Ive recently sprained my ankle and broken my toe, lol. I still am getting great results though because i mix it up.
If you enjoy Tae bo you should really still do it every week, but trying other activities can work the body differently. Yoga and pilates for one are low impact but they use your body weight to train you, improve your posture,breathing and form. Trying medicine balls, kettle weights, strength bands, stability balls, etc....simple props can diversify your routine and target muscles you didnt know you had.
basically the rule of thumb is that if your doing weights you want to alternate days on different areas but cardio can be done every day. You will have to up the intensity or diversify the logistics of every routine you do eventually until you hit a goal weight and then maintain.