First things first: This's experimental and we take no responsibility for what you do to your computer with these instructions.
With the release of the Lion Beta, the Mac OS now has support for TRIM use on SSDs. TRIM allows SSDs to perform better by erasing unused data sectors ahead of time.
Hardmac was first to document the process says, "It's now done! we were able to activate the TRIM command on an OCZ-Vertex SSD! First, thanks to armdn, a member of our forum for telling us about the solution found by German and/or Russian Mac users. He was able to activate TRIM on his Intel SSD."
"TRIM is a command that was implemented very recently in Mac OS X, so it's still hard to tell whether is really makes a difference. Theoretically, this command prevents the disk from decreasing in performances while it's filling-up.
Also, we can only see that TRIM is marked as active in System Profiler, but we don't have any proof that would allow us to say for sure that it's really active.
In the next few weeks, we'll keep looking into and we'll keep you updated on what we find."
Oskar Groth, also known as Cindori, built a script to enable any SSD on 10.6.7.
However, some enterprising users have been able to get TRIM support on Mac OS X 10.6.7
Download: TRIM Enabler