Oh the joys.. for an OCD storage clean away nutter like me the ability to let my kids make mess with no dramas from Mum has been bliss. This came about as a result of having them share a bedroom and I am so glad we did as I have a toy free living room ;)
I maybe go in once a week and return a few things to original spots but generally they seem to pack stuff away themselves or they leave them in little collections that just look cute so I don't mind.
Do you have playrooms? I am loving it...now just to get them to stop watching my TV ;)