pronunciation: noo-kle er, nyoo
-- Webster's New World College Dictionary
I was curious to see whether the dictionary sanctioned the pronunciation "nu-CU-lar." It does not. Though I have read some interesting explanations as to why the president and others pronounce it that way, including this 2002 article in Slate.
Understandable, perhaps. But at least Webster's still supports my skin's decision to crawl every time I hear this.