Sorry Crimz, don't think you'll get too many people on your side with this argument. I'm with you all the way, but if you let your wife take advantage of you at the start, you'll have to live with the addage, "Old Habits Are Hard To Break". Why should she clean up the house when she knows if she leaves it a mess, you'll come behind her and do it for her? Sounds to me like she has you trained pretty well.
If you don't like living in a pig sty, put your foot down and give her an ultimatum. Want to go and play with your friends after school little girl? Clean your room first! Sweep your bedroom and bathroom floors! Go downstairs and put the dirty dishes in the sink! Bring your dirty clothes downstairs and start a load of laundry! If you don't get your chores done, you don't get to leave the house. That's what I tell my teenage kids.
If that doesn't work, then go with the other suggestions here - hire a maid. Take the cost of the maid out of your wife's 'allowance', which I assume you give her money to spend since she's a stay-at-home Mom. When she comes to you and asks for some cash to go out on these 'girl's night out' endeavors, just say, "Sorry honey, I'd give you some money, but the maid did such good work doing YOUR job, I gave my extra cash to her." You'll have to sleep on the couch for a week, but it'll get your point across...