I doubt that SSD drives will overtake hard drives any time soon. Not enough capacity and still too expensive. I wonder if/when we'll see holographic storage & memristors in the consumer market.
Something I'd really like to see is a SSD RAID. Just curious how performance would compare, especially against 15,000 RPM SAS drives. I know SSD would not have any where near the storage, but speed would be the interesting part. I also checked, and Secure Digital cards would fit into a 1U enclosure.