Finally someone other is doing a m-atx mobo with Intel X99 socket! According to TPU, ASUS is ready to go with the new ASUS X99M-WS
The board includes one PCIe 2.0x 1 slot and a single PCIe 2.0 x16 slot (wired at x4) and 8x SATA 3.0 ports + 32 GB/s M.2 slot.
Regarding the I/O ports we see 2 USB 3.1 ports, 6 USB 3.0 ports and 2x gigabit Ethernet interfaces, 802.11 ac WLAN, bluetooth 4.0.
Imho looks like one of the more interesting mATX models since is for "WS" and without gaming features. Can't wait to see more pics (Marc? *cough* *cough*)