I'm starting in the webdesign universe and i used DIVs inside LIs with no problem with the semantics.
I think that DIVs aren't allowed on lists, that means you can't put a DIV inside an UL, but it has no problem inserting it on a LI (because LI are just list items haha)
The problem that i have been encountering is that sometimes the DIV behaves somewhat different from usual, but nothing that our good CSS can't handle haha.
Anyway, sorry for my bad english and if my response wasn't helpful haha
good luck!
