I think this article adresses the criticism from the 2500$ build perfectly. The arguments against trip SLI were all adressed, and even people contradicting themselves got answers that make sense.
People are always gonna critisize choices made in these articles, and make assumptions grabbed out of thin air without any form of proof or facts to back up their statements, imo this article and the 2500$ build made some really interesting and compelling points and pointed out the advantages and disadvantages of both.
Of course I would love to see a 2 x 260 SLI vs. 3 x 260 SLI to see how much that last card really gives, since that's what we are really talking about how much a third GPU really stacks with the others. But since THG already has the GPU charts (http://www.tomshardware.com/charts/graphics-cards,1.html) which I assume/hope is getting a updated very soon based on a Core I7 machine, all these speculations will basically be answered by this.
This article is about a 2500$ build and what solution is best for this, and as seen in this article the best decision when going for playable framerates is trip SLI core 216 260's, not dual 280's which only boost your already enormous frame rates on other games.