I was seeing this in Mavericks, and wound up reverting to Snow Leopard. Saw it against last night, this time with Fusion 7.0 Pro and Yosemite 10.0.
Just upgraded to Fusion 7.0.1 and Yosemite 10.10.1. Now I'm seeing an extreme slowdown. Researching if this is the same as the interrupt storm bug that was reported elsewhere, and which I'd had to work around in 10.10.
I have not put my computer to sleep since upgrading. Will report back if the corrupt sleep image bug is also still happening.