As of now, we don't have any formal criteria regarding online only.  However,
I do know that our librarians are concerned with the archiving aspect of an
online title.  Meaning, if we subscribe to the title for 10 years then decide
to cancel it, will be entitled to those 10 years of online access for which we
paid.  As an example, because of Project Muse's archiving policy, we did
decide to cancel our print subscription to any titles available through them.

Kind Regards,
Laura

Laura Vogler
Serials Manager
Wabash College Library
301 West Wabash Avenue
Crawfordsville IN 47933