OpenBSD was never meant to be a desktop BSD. You should take a look at FreeBSD instead.
They all suffer from the good enough but not mainstream enough problem, i.e. official Nvidia drivers that are not officially supported.
To hell w/ NVidia. If they won't play ball, I'll spend my money on an arguably slightly lesser performing product that is more open.
Though, currently the linux emulation layer in CURRENT has a change that broke the linux Flash binary. I've been flash-free for about 2 weeks now. I can't decide if that's a curse or liberation. Otherwise, I personally think FreeBSD is a mighty fine desktop OS. ZFS is really nice.
It made for an amazing mailserver last I tried it though. I used 3.4 on an ancient P4 with maybe 256MB of RAM an 8GB hard drive. Turns out that was way more computer than it needs, and it was so stable I began to think of it the same way I think of my router.
And I don't think the users of other BSDs have much need for 3D acceleration..
Where would people find this out? Has anyone listed the BSDs and said which task each was meant for? Are there any good BSD-to-BSD comparisons being done now?
NetBSD - portability. OpenBSD - security. FreeBSD - performance and usability.
With that said, no, that definitely does not mean that each flavor can't stand out in the other two fields. Heck, I used OpenBSD as my desktop OS for 2 years on and off, so I know very well how capable it is "off field", and looking at the most popular flavor in BSD-powered server parks we see FreeBSD instead of OpenBSD contrary to what logic might try to dictate.