SS 2005, Win 2003 Server, running under ESXi 4.0, 3ware controller, Crucial SSDs.
We started out with one 3ware 9650 controller that apparently could not keep up and so it corrupted our databases. We worked with 3ware support and we are now also running a 9750-4i to run these SSDs in RAID, leaving the 9650 for the spindles. I have yet to move any files back on to the array for testing. Make backups AND pay attention to what is going on in the environment. You best be running DBCC's and staying on top of it. Work with the vendors and manufacturers as much as possible - even if you spec everything out with plenty of fudge, you just never know.
My opinion would be that the most prominent performance boost would be from tempdb and log files being on the SSD. Since changes are written back to the db file lazilly does it make sense that it is not as critical to have them on SSD? But I guess it all depends on whether your heavy transactional or heavy reads.