Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of China MediaExpress (Nasdaq: CCME) jumped 16% today on an apparent short squeeze.

So what: There wasn't any news out from the company today, but TheStreet.com highlighted China MediaExpress as "The Biggest Short Squeeze of 2011" in an article early this morning. And $125 million of the company's stock has been sold short.

Now what: Auditor Deloitte would agree with many investors who say the company's financials are just fine. The company has hit our "popped" list many times and certainly isn't a stock I would want to short right now. Be careful buying around short-squeeze days because price action can swing wildly in both directions. Long term, I do think this stock is a winner. I just hate buying on an up day like today.

Interested in more info on China MediaExpress? Add it to your watchlist.