Well, depends on what you call "primary".
-My laptop at work gets shut down every day but it's not technically a reboot, it gets "rebooted" whenever I install a patch or software that needs it.
-My 2008 box which I also use as my desktop I reboot only if I really, really have to since it has so many VMs running on it. In practise it starts acting weird if I leave it on for more than a couple of months and needs to be rebooted. Probably a memory leak somewhere.
-My UNIX boxes gets rebooted about twice a year if an important patch comes out, or I'm testing something.
I gave up the penis growing max uptime game years ago, I hit 450 days on a Linux box once and it only went down after a powercut. I'd rather have a current security patch, thanks.