The firmware and hardware released last Monday. See the below excerpt from the current firmware release notes:
2.5” SATA HDD and 2.5” SSD Dependencies:
1. The AXXTM3SATA board and bracket assembly must be attached to a 2.5” Solid State Drive (SSD) or a 2.5” Serial ATA (SATA) hard drive before the drive can be used with the Intel® Modular Server System MFSYS25.
2. To ensure the integrity of the 2.5” SATA HDDs the Power Supply version must be at D73299-007 or later and the IO fan module must be at AA91260-004 or later.
Note: Only supported HDD’s should be used in the Intel® Modular Server System MFSYS25/MFSYS35. Using non-supported HDD’s may yield a non-functioning system. Refer to the Tested Hardware and Operating System List (THOL) available for download at: http://www.intel.com/support/motherboards/server/mfsys25/
The latest THOL we can find on the site is from July 2009, and it doesnt reference any SSD models: http://download.intel.com/support/motherboards/server/mfs5520vi/sb/mfsys25_mfsys35_mfs5000si_mfs5520vi_thol_rev2_1.pdf
However, the readme below seems to imply that at least one model of SSD is supported.
The THOL seems to be lagging because I know that the Seagate Constellation drives are also validated, but not listed.