Estimates of Conventional Journals, OA, and Repositories?

["David Davis" <ddavis@copyright.com>]

David Goodman's recent presentation at SLA put the question of scholarly
publishing futures into the context of 'relative use', as among
Conventional Journals, OA Journals, and Institutional Repositories. This
sounds about right to me. Those are indeed the trend lines to watch. Yet
'relative use' seems like a difficult metric to assess in detail.
(Alternatively, I'm just overlooking something obvious; that happens, too.
;-)

Does anyone have (or have a reference to) hard estimates of the current
totals for Conventional Journals, OA Journals, and Institutional
Repositories? If so, please post to the list.

Thanks.

Dave Davis
ddavis@copyright.com