This would be a nice review. I don't know much about Asus boards so it would be educational for me. I know of Asus' reliability, so they are in the running for my next (DDR) board.
About your question "will an Asus videocard run better w/an Asus motherboard?" The answer is "no." Asus sells their version of NVidia GF-family cards. The card is based on a "reference design" Which basically means that 20-different manufacturers follow a schematic, build the board and slap their name on it. Usually, any reference-design board will perform no better or worse than another. An Asus videocard will work in an Iwill mobo, for example. Hope this helps.