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 newspaper and media company The New York Times Co. (NYSE: NYT) jumped as much as 12.5% today on above-average trading volume.

So what: Mexican multibillionaire Carlos Slim has long held a large stake in The Gray Lady, but recent SEC filings show that he upped his interest from 7.5% to 8.1% with another batch of buys. Slim, who is currently the world's richest man thanks to his interests in Latin American telecoms America Movil (NYSE: AMX) and Telmex (NYSE: TMX), clearly sees opportunity in The Times.

Now what: On the face of it, The New York Times appears headed for obsolescence in the face of onrushing Amazon.com (Nasdaq: AMZN) Kindles, Apple (Nasdaq: AAPL) iPads, and other newfangled ways of consuming media that don't involve ink and paper. But it's not too late to join the digital era. Slim's fellow ultra-Croesus Warren Buffett also likes this sector, as shown by his commitment to The Washington Post Co. (NYSE: WPO). And neither the Slim empire nor Berkshire Hathaway (NYSE: BRK-B) was built by Luddite losers. If nothing else, these publishing stocks sure look temptingly cheap.

Interested in more information about New York Times Co.? Add it to My Watchlist.

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