real review of an X38 board has appeared online and it's of the Gigabyte X38-DQ6, the same board that Anandtech did a preview of a couple of weeks ago, although this should be the final version of the same board.
This is the DDR2 version of the board though and it looks like Gigabyte has a different design for the DDR3 version as far as we can tell. The DDR2 version lacks eSATA and has an additional pair of USB ports and a mini FireWire port in its place.
The reviewer wasn't that happy with the overclocking performance of the X38-DQ6 and the performance numbers aren't exactly brilliant compared to Gigabytes P35-DQ6 and P35T-DQ6, the latter with DDR3 memory.
You can find the full review here