Natural gas is on a tear. This is the live 24h chart for December 2010 contracts, please take a look at the prices between Thursday/Friday and today.
This change was over the weekend. We will see what UNG and HNU do at the open and during the day.
UPDATE 10:20AM: UNG was up 1.9% in pre-market as of 7:30AM, and is now down 2.2% after the market opened. The day is young however. This is interesting, since we are now using December contracts, we wonder if UNG had anything to do with this drop after the open. Please see this post for UNG rollovers vs futures..