Well, the question is how long OpenBSD will continue to survive without a modern desktop version. Linux has been enjoying a remarkable growth of support over the last few years thanks primarily to its slow incursion of the desktop market. Can OpenBSD continue to live only as a server / router / network service operating system for the long term? I don't know.

And, even in the server market, it's falling behind in terms of support. The VPS market has gotten really big really quickly; the OpenBSD team has legitimate concerns about trying to run a "secure by default" operating system in a virtualized environment, but unfortunately that point of view has resulted in OpenBSD being completely unavailable on Linode, prgrmr, EC2, Slicehost/Rackspace, etc.

I have no idea if OpenBSD's installed user base is growing or shrinking overall. But, I expect that it's rapidly shrinking relative to the amount of support that Linux is currently enjoying, and that's going to lead to OpenBSD getting less and less upstream support, which is eventually going to strangle the project. The small OpenBSD development team simply won't have the resources to rewrite all of the big upstream packages. (And I'm not talking about Gnome here; OpenBSD already has its own httpd and its own smtpd, for example.)