Sure, I would be very happy to use it as my desktop. Even donated for them. But it needs more time to adopt more tools at the very least for broader adoption.
Really, anything I've used Linux for on servers I've been able to replicate on OpenBSD... I don't feel like everything is automatically more secure just because I'm using OpenBSD but it's simplicity with regards to package management and system configuration does help me understand just about everything running on the system which, IMHO, does lead to better security.
I'm doing web development for the last 4 years and programming for almost 2. My desktop and laptop have only OpenBSD as an OS.
What do I miss?.. apart from some more recent games (which is the reason I have a console), nothing[0]. ;)
As for hardware problems? Well, if you want to run some new (for you) OS without doing some homework (will it run? what problems are unresolved for X hardware? what hardware do I already own? will it cause problems?) you're out of luck even with Linux in some cases.
Hell, even my x41 single core laptop can play 1080p video files.
[0]: http://openports.se/
[edit]: also, upgrade process => ~3-7mins (depending on hardware). Can't beat that. :)