I have it running on my home fusion drive (Fusion of 160gb Intel SSD + 1TB spinning drive). I did get a strange error about not having enough space on the logical volume to install it, but I just clicked ok and the install continued.
I think there is a issue with TRIM, but those reports have always been overblown. I'll just wait for the TRIM enablers to be updated.
Semi-related, I updated to Yosemite on an un-Fusioned drive and it went fine. I just had to choose my drive when upgrading. I like choosing what goes on SSD and what doesn't. Having it automatic made me nervous so I got rid of it.