And just read an article at anandtech that seemed to suggest that secure erasing was the pertinent thing to do, but this was a wee while ago - other people seem to be saying its not necesarry (only an issue now because I went ahead and installed the OS)
Some SSD's will support the "trim" command. That command allows the SSD to release free blocks without having to do a rewrite. That improves performance and increases the longevity of the drive. Intel X25-M gen2 has the capability, while gen1 does not.
If you have windows-7, it is capable or passing the trim command to the SSD provided that the ssd is in SATA AHCI mode. You will then get the windows AHCI drivers.
If you install in IDE compatibility mode, or raid, then you will get motherboard drivers which currently do not pass on the trim command.
For a clean install, you might want to reformat, but I see no need for a secure erase which will beat up your ssd for no good purpose.
I think it is better not to use raid for a SSD. I tried raid-0 and found that while HDTACH runs were impressive, actual performance was not improved.