I apologize if the answer to this question is obvious, but...

The DFI INFINITY NF ULTRAII-M2 Newegg link has two PCI Express x16 slots, but does not state explicitly that it supports SLI. It is based on the NVIDIA nForce4 Ultra chipset.

I'd like to purchase this board to build my new system, but I have not been able to find any reviews of it at all. I do not plan to use SLI initially, but it would be nice to have the option in the future.

Advice is appreciated.

It won't support SLI officially, but if you read the site below there are ways that you can use to enable SLI:

http://www.pcmoddingmy.com/e107_pl [...] tent.377.1

Yup. You can either softmod it or hardmod it.

Softmod: Download the modded forceware drivers and you're done..... Only con is that each new driver that comes out must be modded for SLI.

Hardmod: You have to soldier two parts of the NF4 Ultra chip. Cons are that you void warrenty and can badly mess up if you aren't careful. Pros are that your chip is now identified as an NForce 4 SLI.

The second PCI-E x16 will run at x2 though. In benchmarks you'll go down a few points but according to real-world tasks (games, etc.) it doesn't make a difference.

Heres the soft mod you need to run it.
Its still a very worthy motherboard despise of this small setback. It overclocks very well, its rock stable and has a great $/performance ratio.

I actually have a link to another way to mod it to use SLI 8*8 :
Mod
There it reads: "With a simple conductive pen job, I enabled SLI function on this bargain board! Like with the LAN Party Board, shift the 6 bulky jumpers below PCIE slot 1 down to switch to PCIE x8 x8 for SLI running."
Can anyone verify this?

It will work too. That is the Hardware mod agi_shi talked about.
But due that theres more ways you can screw up with a hardware mod I recommend the software mod.

uhh just to let you guys the hard mod with the nforce 4 ultra was taken away by nvidia quite a while ago if i remember... you pen 2 resistors together on the top of the northbridge. in newer revisions of the nforce4 chipset nvidia started hiding the 2 resistors under the IHS.... that is what i remember please do not yell at me if it isnt right... just a heads up..