You question is a good one. It seems trim is supported in Windows 7 but currently none of the ssd’s currently on the market can support it. For a currently available ssd to support trim on Windows 7 it would need a fw update and also the controllers would need to be updated.
A number of ssd’s provide a standalone beta trim tool, however these are all based on the same controller and they suffer significantly more from degradation than the Intel drives.
It would be really interesting to know how native trim support in Windows 7 will work. i.e. when will it delete “deleted” cells. The standalone trim tool is a nice solution in that it coudl for example be used to wipe cells quickly after boot up, leaving the drive ready for optimum use.
From my experience raid 0 does not result is better performance in real life applications, even though benchmarks show a significant gain. Whilst I have got the X25-e’s I only use them for desktop use and I only use raid 0 for additional capacity. If trim is not going to work in hard raid I would seriously need to consider going to one larger ssd.
As far as I know none of Intel SSD's support trim ATM. Some other vendors' product, like the OCZ Vertex and latest Summit models do so. Vertex has an on board ARM processor as the controller so it is an easy shot, while the Summit series feature the new Samsunk MLC controller that does trim processes in the background when the drive is idle. Though the Vertex do need a suitable OS (like Win7) to trigger trim method call because it is not spontaneous like the Samsung controllers' method. I read a lot in this topic and it seemed that OCZ support forums do have a lot of useful information.
RAID users are a little bit messed up because trim method call needs to be passed to the drives by the raid controller. But till raid controller updates come, you may try the method described here: http://www.ocztechnologyforum.com/forum/showthread.php?t=57888