It has worked since day one with the first developer preview. Performance seemed normal but I didn't get crazy with the testing. If there's anything we learned from Mavericks it's to wait a while before upgrading.
I updated Yosemite pretty fast after release on my macbook, but not on my MacPro, since I usually use the first mostly private and the latter primarily professional (I'm a very occasional VJ, primarily editor/animator). But of course, only days after updating I was asked to do a VJ gig, so I had to do it with Yosemite. While testing, everything was fine, but after hooking up in the club, things started to run laggish. The video output (Mini display port > VGA) didn't work at all at first (I had to turn the resolution WAY down). and mixing went kinda well, but every time I added a 4th layer, the program crashed! Luckily I used a lot of dark sequences which turned to black very often, so it wasn't very visible that it crashed during the show, but it was pretty annoying.
I reinstalled Mavericks, and everything runs fine again. hope Resolume will come with an update very soon.