Mine was canceled too and I ordered at 3:30 AM CST so I damn well know they had stock. I got the e-mail as I was driving to Westmont and ended up rushing to Central store before opening and got one of the two last ones.
I'm in the same boat as you on Asus P8P67 boards since I already have Megahelms. I don't think I can install a fan on the DIMM side if I want to use all 4 slots. And, I'm not sure if the heatsinks on the opposite side will get in the way of the fan.
I like the Asus over the Gigabyte due to...
Asus will have a Maximus IV Extreme with the black/red scheme. It's not listed on the Asus' US site yet but it's on the Asus global site.
http://www.asus.com/product.aspx?P_ID=AoHE7iDJrYucOm0n&templete=2