From what I've read, including the above link, there is some general skepticism about this claim. The code audit that followed the allegations seemed to help iron out even more bugs, making openBSD even more secure.

Further info here: http://www.itworld.com/operating-systems/131505/openbsd-chie...

And here: http://marc.info/?l=openbsd-tech&m=129236621626462&w=2