Up until now, the largest mSATA SSDs have topped out at 240GB/256GB, but Mushkin is now announcing their 480GB SF-2281 based Atlas mSATA drive.
Specifications for the new Atlas mSATA drive are what you would expect from a modern SandForce 480GB offering. Trim, ECC, SATA 6Gbps, upgradeable firmware, and all the other usual suspects are present. Mushkin is using "high speed MLC NAND", just like virtually every other modern consumer SSD, and the Atlas comes with a 3-year limited warranty. Max read speed is 540MBps, write is 425MBps, with 78K random read IOS and 28K random write IOPS. It uses the MO-300 mSATA form factor (50.80 x 29.85 x 4.85mm). Availability is expected in this Month with an MSRP of $500. That's higher than 2.5" 480GB SF-2281 drives by $50-$150, but that's the price we pay for smaller form factors.