First, an anti-conservative organization isn't exactly an objective source--and MediaMatters in particulary is well-known for, well, sucking.
Second, MediaMatters notes--in order--Novak, a conservative columnist (note that Novak almost certainly meant the Deficit rather than National Debt--since the deficit as a percentage of GDP
is lower... but either way, he's not a journalist, he's a columnist); a piece that also has the correction acknowledging it was incorrect at the bottom; an unreported poll which, not being able to see the poll myself, I can't say said or did not say what they claim it does (although the law of averages suggests it didn't), that came from someone giving them 4 days to report it and then running the critique; a writer pissed that CNN didn't report a "Bush Flip-flop" that the
New York Times reported--a perusal of the NYT article shows that the "flip-flop" doesn't exist; and a piece that claims Stossel relied upon one study to find a result when there were actually several such. Six non-exmples out of six "examples"--not a very good record.