SSDs are rather new, so I couldn't find this information on the Internet.
Would the performance of a local hard drive connected using SATA2 get out performed by a SSD over gigabit ethernet?
In terms of both latency and bandwidth, mechanical hard drives and local networks are very similar.
The SSD would over course be SLC or Intel's MLC. Not a cheap MLC.
As for usage, think typical computer user with some multimedia. Let's say its a regular computer with mechical hard drive vs a diskless computer that boots off a USB stick and then loads the OS off a SSD over gigabit