It was bad enough when George Bush was the one who seemed unable to pronounce "nuclear" correctly. But lately, a lot of TV news people seem to be doing it too.
As noted on Metafilter, Geoffrey Nunberg complained about this quite some time ago.
A couple of sites offer help to anyone wanting to learn proper American pronunciation.
But sometimes the battle is too much: Ruth Walker at the Christian Science Monitor has given up on some mispronunciations.