Hi Jenn
My initial reaction is to be accept their apology and leave it at that. It sounds as if you went about mentioning quite diplomatically, and in turn they have been sensible and apologetic. I think if they'd left a load of rubbish (ie half eaten food, dirty clothes etc) around it may have been different, of if they were actually there asleep when you arrived!
Also, I think sometimes it's useful to have something like that up your sleeve, just in case we do something to upset them in the future without realising it.
By the way, good ideas about the databases.
See you next Thursday.
Dawn