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: Is there anything tastier than Russian kefir? Not according to PepsiCo (NYSE: PEP), which anted up $3.8 billion to buy a majority stake in local kefir kingpin Wimm-Bill-Dann (NYSE: WBD) this morning -- sending Wimm's shares soaring 27%.

So what: Pepsi's been dueling with Coca-Cola (NYSE: KO) for control of the Russian drinks market for years. The companies have mainly been nailing down the juice market, and Wimm's got a hand in that, and water as well. But now Pepsi's leashed the big dog of Russian and Ukrainian dairy, the biggest name in milk, yogurt, and kefir.

Now what: Following its offer to buy 66% of Wimm, Pepsi will invite all other shareholders to tender their shares at the offer price -- about $33 per ADR. Therefore, if you missed out on the initial share price lurch, there's probably only about another 5% of profits to be had here, and only if the Russian Anti-Monopoly Committee approves the sale. There's always the possibility a bidding war will break out, but so far, Coke and Pepsi have avoided stepping on each other's toes in Russia. Dr Pepper Snapple (NYSE: DPS) has shown little interest in the country. Lifeway Foods (NYSE: LWAY) is too small to compete, Dean Foods (NYSE: DF) too poor, and Danone turned up its nose at the chance to buy Wimm six years ago for a 1 times sales valuation. It would look quite the fool (lower-case "f") if it turned around now and raised its bid price past Pepsi's offered 2.2 times sales.

Basically, if you didn't own Wimm-Bill-Dann before today, there's little reason to do so now.

Want to watch how this all plays out? Add Wimm-Bill-Dann to your watchlist.