Source to where bethesda outright said that.
Found one from Todd Howard.
http://www.gameinformer.com/b/news/archive/2012/02/16/bethesda-knew-about-ps3-skyrim-issues.aspx
Also, for that other guy, I found out who the Obsidian employee was - Josh Sawyer.
http://uk.ps3.ign.com/articles/121/1213924p1.html
From what i've read, Bethesda tried refuting his claims by saying that they had fixed the lag long ago, lol....