Thats looks like Asus Maximus VI Extreme Haswell Z87, if its anything like the Ivy Bridge version ASUS Maximus V EXTREME LGA 1155 Intel Z77 HDMI SATA 6Gb/s USB 3.0 Extended ATX Intel Motherboard
, one of its features is that unlike all Z77 boards, it comes with 2x 16xPCIe, check the back (remember the NDA is still on so im not even sure if the Z87 has dual 16x slots as default like X79, but i somewhat doubt it, thinking we will see Ivy Bridge E, so they have to mantain the X79 differentiation),
In theory the first two reds should be the ones to use on that mobo for SLI, not sure if it will work using first n last.
Now this is $400 motherboard, its more meant for heavy overclockers, so my suggestion is to check the hero version, as it will be a little cheaper and has different disposition of the pci e slots that might play better, it probably wont have have twin 16x pcie like X79 board.
Back to the hero version here is a layout of it,
If you want triple slot spacing between your GPUS, you are going to need an Extended ATX motherboard, like EVGA Classifiend, etc. Or drop the LSI card, the Z87 mobos like the ROG series come with 6-10 Intel Sata III (i believe not sure as until the NDA is lifted no one knows for sure), but if it is like that you can probably control 4 pin drives and the 2 ssds via the intel built sata controller, do you use the LSI for raid?
Personally i would suggest against SLI, as it will introduce more heat to the case and increase the temp inside, meaning it will either run hotter or you will need to increase the speed case fans to compensate. Second, even when scaling on SLI is really good, its totally dependant on drivers, so you will have to update constantly, and hope that whatever you play gets supported, this is not a big deal as i also update constantly when im planning on playing games on release with a single gpu, but its a little more complex for sli, sometimes you get extra things like microsuttering etc, this are avoided most of the time on single gpu setups. The only reason that personally will go into SLI is when 4k monitors are release and are sub $2k, as driving 4x 1080 is going to be hard... probably a SLI of whatever is currently available will be good idea for those who enter first the 4k market... but there is a huge reward vs risk, much more pixels =) so im willing to deal with more issues for much better experience, but this is still far, maybe a gen or two of GPUs.
Now if you are entering SLI because you want to, and you want to experience whatever it brings.... then go for it, there is nothing better for me than learning and enjoying this hobby. But this gen, im only going for single GTX780, its going to be 20% faster than GTX680, probably around 40% faster than my GTX580, that should keep me good now than im running 2560x1440, i have no super hard rendering games in the horizon, just Neverwinter, LOL, DOTA2, Diablo3 and SC2 takes my time, none of those are that demanding that will requiere sli.