Ha! We have this issue at home too. DC keeps her room FAR neater than her standards for the rest of the house. Most days, I'm just happy to have a kid with a clean room but other days we have talks about her doing a better job with the rest of the house. But, part of why I don't come down on her for that is because we ALL tend to leave the rest of the house pretty messy. Sometimes I'm tempted to gripe about the number of DC (or DH's) shoes in the living room...till I do a count and realize that I've got a few pairs of my own.
Yes I'm not entirely innocent either :) It's very, very hard to cultivate tidy children when one is not naturally tidy one's self. On my own, I am actually fairly good - but I find that tidying up other peoples' messes (*cough* DH *cough*) to be mentally draining. Where do I put things? Where does he want them? How do I keep track of things in my head so if I put them away they're not "lost"? Occasionally I'll just collect everything up and dump it in his office, but that usually backfires because he just shunts everything back out into the hallway, which creates a bit of a fire hazard for exiting DD's room :(
The problem is that DH works long hours, and he does a ton of stuff around the house in terms of renos and fixing things. His time priorities aren't my time priorities though.
Anyway, total digression - the point being, it's really hard to get DD to clean up her stuff when she's got poor role models asking her to do it. HOWEVER I did find a partial solution this weekend - I invite my sister over, have her sit on the couch, and THEN ask DD to tidy stuff up. All of a sudden she's more interested in looking good for Auntie Rachel than arguing tidying strategy with me, and bam! we can see the coffee table again. Good thing Auntie Rachel lives in the same city as me now!