Everybody enjoys a good snarkfest, and these guys are particularly good at it. But those who are taking delight in seeing Sal Khan get "taken down a peg" are completely missing the value and innovation here. To me, the important thing is that these guys have adopted one of Khan's signature moves---short, low-production-value, personal web videos---to critique pedagogical technique. This has great value for math teachers who may miss some of the finer points of math instruction (e.g., consistency in terminology) that Golden and Coffey point out in their review. It's basically a Khan Academy-style lesson for teachers, and it should be able to scale in production just as Khan Academy itself has. I would love to see many, many more video reviews of instructional materials on the web.
To their credit, Khan Academy has taken down the video in question, presumably to improve the video based on the critique. One of the premises of OER is that people will improve the quality of materials. The assumption is generally that they will do so themselves by editing, but this is a demonstration that just having the content out in the open where the author can get feedback is of great value too.