Solid State Drives (SSD) are growing at a rapid rate. The latest information states 510 Million and growing 50% over the next year. This is still a small number compared to traditional hard drives and Seagate just released a hybrid to enhance hard drive performance. Solid state technology is going down in cost and the controller technology is advancing to make SSD more attractive in more applications. Solid state technology does have a strong appeal as everyone knows that the more moving parts the more likely you will have a failure.
Here are a couple of articles on SSD Drives:
http://www.reportlinker.com/p0196489/Enterprise-SSDs-Technologies-and-Markets.html?request=news
http://hothardware.com/News/5Way-SSD-RoundUp-Sandforce-vs-JMicron/