I see a bunch of uses for new SSD, but sure, not important for most FPS gamers that use their computers just for that one thing.
I have a computer in my office downstairs that would be great with SSD. The room has a big ass parrot in it. I don't know if you know it, but nothing is dirtier than a bird. They put TONS of sticky dust stuff in the air. I have it on a 10 minute sleep timer so it's only running fans when I'm in the room using it. It comes back up in 30 seconds or so. I'm sure that'd be sped up with SSD. Too bad this stuff wasn't mainstream a couple years ago, that computer would be on a 5 minute sleep timer and a lot lot less dirty than it is. I'm building one for a friend that was clogged to hell with dog dander. He keeps it off all the time, but I'm sure with this new one he'll keep it in sleep.
Diablo 2, you get the drops faster than everybody else because every stupid video that has to load goes instantly, not sometimes when your HDD is in the right position to read the animations/videos that the game freezes up until it can display.
Photoshop/4channing/ytmnd use, you're gonna be able to open that pile of editing software a lot faster to make those stills, gifs, and audio, etc. Unlock that taskbar, beotch!
Playing music while gaming. I never do it. But when I'm SSDed up, I will.
In the future, when we get to using coreless chips, SSD is going to be practically required to keep up with them. But yeah, that isn't too relevant to paying $200-500 on an SSD today.
I probably left out half of what I was going to say. But yeah, if you're just gonna play FPS all day, you might literally never even notice the difference in performance. If you're doing work on your gaming computer, yeah, it'll take out all those 5-15 second waits when you open or close those huge hog programs and that could be sure be worth the money to a guy that doesn't see it a big deal to spend $200 on a drive when he makes a couple grand a week and uses the computer to get that cash.