I have an x25-m G2 80GB and a crucial M500. The crucial drive has substantially better random iops, and the system does feel faster booting off it than the x25-m. But the difference in "feel" is like a 7200rpm platter drive vs a 10,000rpm platter drive... same ballpark but the 10k is just a bit snappier.
Newer SSDs are definitely faster than earlier ones, but we've kind of hit a wall with needs for even more speed. The slowest (non-broken) SSD you can buy today will be no less beneficial in real world home-user operation than the fastest SSD you can buy. Its just that there is a little bit of room for improvement over 2008-2009 era SSDs. (Don't take this as a disagreement, just an elaboration).