For those of you considering using SSDs on your servers, you may want to also consider the ioDrive products from Fusion-io.
This company makes enterprise-class storage on a board populated with flash and managed by their own supposedly-sophisticated drivers. The board + drivers are meant to get around the problems of SSDs, such as write-failures. They make both SLC and MLC products, at different sizes, to meet different budgets and purposes.
I tried them about 3 years ago on a database server (not Postgres). The real-world speed was excellent, yet disappointing in that it performed as well as our high-end RAID-10 from HP. We were looking for even more speed, and were promised that, but did not see it in our trials.
• This was using their first attempt at Windows drivers.
• We may not have tuned the settings properly.
In the end, we chose to keep our RAID for the time being.
So, while I can't specifically recommend their products, I certainly suggest considering them. They have drivers for Linux and Windows, but apparently their rumored Mac OS X drivers never came to fruition.
Other benefits beyond speed include size, power, and heat. An internal board with flash saves on all three, compared to a RAID made of either discs or SSDs.
As an aside, this company is also known for having put The Woz to work as their "Chief Scientist". This may be the closest he's come to a regular job since leaving Apple.