Kongo vs Barry got my vote. All of those are awesome KO's, but I think that Jon Makdessi vs Kyle Watson deserves an honorable mention for the spinning back fish KO.
EDIT Almost forgot Wandy vs Le. Le's nose looked ridiculous after that fight, although probably not KO of the year.
makdessi's ko definitely came to mind but because watson is a low level fighter i chose not to use it. in a best ko's of 2011 thread it would be there no doubt. but not in a poll for thee best ko of 2011. but it definitely deserves an honorable mention. i would've put barbosa's ko over etim as a candidate too but that was last month. maybe it will be on a best 2012 ko thread
btw, here is the makdessi ko, @ around 0:17
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