We always put used towels and bed linens together on a hard surface floor (bathroom or, if at OKW, in the laundry room. Trash is in cans, which includes any open food items. Unopened perishables we leave, and from a conversation with mousekeeping understand that the staff will use items which are unopened and appear to be fine (in that case we had cheese and lunch meat which we hadn't gotten around to using for sandwiches since we were working on the goal of eating our way through Epcot!).
Obviously it is easier for mousekeeping to do their job correctly if the beds are stripped or at least unmade. Otherwise I think they may be unsure if they were slept in. Same for the dishes, I feel sure that they will run the dishwasher regardless, and actually would hope they would because our dishes tend to look clean even when used (you have to understand, we don't cook -- we use glasses and possibly bowls for cereal, but once they are rinsed and put in the dishwasher it could be confusing since they definitely don't look dirty.
Never used the vacuum and only would do so if we had some unusual spill of chips or whatever. We fork over money for points, dues and tips for mousekeeping, I certainly don't think it is necessary for us to thoroughly clean the unit, also, particularly since most of what we could do would be done again by the cleaning crew.
