I guess my take on SSDs would be that they're likely perfect for TempDB. As previously mentioned, they may also be perfect for a database other than TempDB if and only if you have the log files on permanent storage and you're doing some proper point-in-time backups.

I do, however, want to remind everyone that everything has a limit. While you might get a 20x improvement in the performance of current crap code, there is only so much CPU to go'round. The use of SSDs should never become a "good enough" reason to promote crap code to production. To wit, Development, Test, and Staging boxes should never have the databases on SSDs IMHO.