I'm not using one in a production web environment, but my Macbook Pro has one in it now and it's phenomenal. Photoshop boots up in quite literally 3 seconds or less (cold startup) and every other action imaginable is noticeably quicker. I used to feel like browsing files in the Finder was slower than it was for me on my old Windows XP machines but eventually I got used to it. I use keyboard navigation as well, so it felt even slower. (For anyone interested, arrow keys, and command+downarrow to open a folder, command+uparrow to go to the parent folder).
Now that I've got an SSD as a boot drive, navigating the Finder is significantly faster. It feels so quick. Folders open instantly. When I got my development environment up and running (nginx, uwsgi, django, mysql, etc...) I noticed that code compiles wayyy quicker too.
Love it! For the record... I've got the Intel X-25M, second generation. It's only 80GB (they're pricey!) so I also picked up an MCE Optibay which is basically a hollowed out superdrive that lets you mount an additional HD where your DVD drive sits. It also includes an external enclosure so that you can put your otherwise useless SATA DVD drive to use via USB. So now my MBP has two drives in it, an 80gb ssd to boot off of and a 320gb regular drive for bulk storage (media, photos, etc..)
Gotta give credit where credit is due... Paul Stamatiou's blog came in handy a few times with aiming me in the right direction with this. Here is a nifty article from his blog, which describes most of what I did other than the RAID part (which I did not do). http://paulstamatiou.com/how-to-apple-macbook-pro-raid-0-arr...