If you ever think that your partner isn't doing as much work as you are around the house, arrange to have him or her go on a week long business trip, and see what you think after that.
I'm only halfway through AND I have my mom here helping, and I am more convinced than ever than ever that Hubby does his fair share around here! I'll confess that Hubby and I sometimes have that conversation about who is slacking off and who is working too hard, but in reality, we're both doing our share. I think that once you add kids to the equation, it is easy to become convinced that your partner is slacking off. Surely if he was doing his share, you'd have more time to yourself!
I'd write more, but it is housecleaning week on our chores schedule, and I need to go clean the kitchen.