Because of the size of most games I keep them on my storage drive, so, for myself, no difference. Some, though, if they have the capacity, put one or two of their favorite games on the SSD for faster load times. That's why it's good to get an SSD with enough capacity to hold more than just the OS + essentials. I have an 80GB, and I like to keep a good porportion of the drive empty to minimize write cycles to individual cells, but if I had a 120 I'd put some of my games on C:
My boot time really is half with the SSD. Hitting the button to a usable desktop went from 1:30 to 45 seconds. (I have a lot of peripherals.)