The DOAJ has just announced a series of milestones, including the milestone of exceeding 5,000 journals!
Kudos to DOAJ. As I point out over on the Imaginary Journal of Poetic Economics, this is more than 20% of the world's scholarly journals that are now fully open access.
This is a conservative estimate - from the OA community, what I hear is a little frustration with the amount of time it takes to get a journal vetted and included in DOAJ. If you'd like to help DOAJ achieve better service - consider joining as a member or sponsor.