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 natural gas storage and transportation company Southern Union (NYSE: SUG) surged 17% today after Energy Transfer Equity (NYSE: ETE) agreed to buy it for about $4.2 billion.  

So what: Shareholders of Southern Union will receive newly issued units worth $33 each, representing a 17% premium to yesterday's closing price. The move will create the nation's largest natural gas pipeline company, and given the pop in Energy Transfer's shares, Mr. Market seems happy with the prospects and price of the deal.

Now what: Investors have good reason to be excited. After the transaction, the combined company's network will span across nearly 45,000 miles and have the capacity to move about 31 billion cubic feet a day of natural gas. When you couple that larger, more competitive scale with already solid operating margins, Energy Transfer shares are certainly worth looking into.

Interested in more info on Southern Union? Add it to your watchlist.

Interested in more info on Energy Transfer? Add it to your watchlist.

Fool contributor Brian Pacampara owns no position in any of the companies mentioned. Try any of our Foolish newsletter services free for 30 days.

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