TV.com's Tim Surette picked Supernatural as one of his Best TV Shows of 2009:
"Let's see, Paris Hilton gets her head chopped off, Grey's Anatomy gets parodied, and Lucifer is a cool guy. The show has found its stride, and all it took was the impending end of the world."
And the series was voted Best Scripted TV Show on E! Online UK (thanks to Supernatural Wiki for the link).
Source: TV.com, E! Online UK.