UPDATE from Punxsutawney, Pennsylvania (02/02/10) ... The world's most famous groundhog, Punxsutawney Phil, emerged before chilly revelers in western Pennsylvania Tuesday to see his shadow, meaning winter will last another six weeks.
Whither winter? There's only one gen-yoo-ine and official representative of Marmota meteorologica that can tell us ... and that's Punxsutawney Phil ..... don't be fooled by imitations.
Here's video from last year's festivities at Gobbler's Knob ...
According to this Wikipedia write-up and the various sources to which it links, the roots of this annual celebration are very old, even ancient, and reach deeper than even the most persistent of groundhogs can burrow.