Wiley (owner of Blackwell) has published a list of the most popular articles in their journals in 2009. It’s hard to know what the definition means, since the criteria are not explicit (e.g. it includes articles published before 2009), and no rankings or numerical scores given.
However, scanning through the list is one article on open innovation — the Enkel, Gassmann and Chesbrough introductory article to September special issue on open innovation. The article — “Open R&D and open innovation: exploring the phenomenon” — is available for free download.
I have a few quibbles with the article (since my friends didn’t send it to me for comment beforehand :-) but overall it summarizes the advances in research on open innovation since the publication of the 2006 Chesbrough et al book Open Innovation: Researching a New Paradigm.
So if someone wants a place to start on open innovation research, that would be a good place to start, as well as my earlier post on the most influential O/U/CI research.