Didn't Juliano Rizzo already post that he'd been able to extract keys from a server? I'm not clear on the circumstances; for instance, it might have been right after boot, and it might have been Apache, and it might have been FreeBSD.
Errata security modified their original post to say that yes they are extractable. And a moderator properly fixed the title after the article was changed to reflect the retraction:
i suspect the memory accessible by this bug depends a lot on the software, OS and possibly hardware, e.g. on openbsd and bitrig amd64, the amount of memory leaked per exploit is less than 64 KB, closer to 32 KB. if you go much past the 32 KB mark on these OSes, it segfaults.
running an exploit script against one of our own services showed only 1-2 KB of information, most if it being the (public) cert, and the rest zeroed out.