SSDs rule. I've had one about 2 years now as my boot drive. Steam is on a spinner drive, as are most games. I usually keep 1 or 2 games I'm playing a lot on the SSD, and the rest on the spinner. Same with programs: I have my browser, winamp, etc on the SSD, and stuff that are really big or I don't care about load times (Office) on the spinner. My SSD is only 80GB, but I tend to have 35GB or so free most of the time. Movies, music, Photos go on either the spinner or a NAS.
But ya, I would never want to be without an SSD now. I keep hoping my spinny drive at work dies.