The Abit Fatal1ty F-I90HD is currently the "best" overclocking micro ATX board for Core 2 Duo. It is available for
pre-order here. It is not a perfect product, but is merely the "best at this time." People have been hitting up to 370MHz FSB (sometimes requiring a modded BIOS) with this board which is really good compared to other mATX boards maxing out at closer to 320MHz FSB. I believe at this time it is not recommended to overclock this board while using the integrated video (use a PCI-E 16X card instead) because a couple of people have had board failures under those circumstances. Since this board is so new, nothing is "for sure."