It's a smaller difference than HDD to SSD, but you will see a difference. When I moved from Vertex2 to Vertex3, it was noticeably quicker. When I moved from Vertex3 to another SATA3 SSD, it was a negligible difference.
I'd go for it.
1100T, Biostar TA870U3+, 16GB DDR3, 240GB Mushkin Chronos Deluxe, 2x1TB Black, 2x3TB Green, 3GB XFX 7970, Antec 650W, CM690, Dell U2713HM & Samsung 2343BWX