...things have changed, and rampant publishing of 
images has caused a lot more clamor about what 
can and can't be used. Generally, if you ask for 
permission, they'll let you; but from what I know 
(and the few companies I have asked; Capcom, 
Pierrot (for my never published Tennimon 
site...::sigh::)), it's frowne upon now...of 
course, I could be wrong, or just have talked to 
the wrong people.

-Misha