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 CapitalSource (NYSE: CSE) soared 20% today after bank holding company PacWest Bancorp (PACW) agreed to acquire the financial services specialist in a deal valued at about $2.3 billion.

So what: The deal values CapitalSource at about $11.64 per share -- 0.2837 of a PacWest share and $2.47 in cash -- and represents a premium of about 18% to its closing price on Monday. PacWest is making the move to expand its presence in southern California, and judging by its own stock's 6% bump today, Wall Street seems pleased with the price management is paying to do it.

Now what: The combined bank will be the eighth-largest in California, with about $15.4 billion in assets and 96 branches in the state. "The combination of these two franchises will create a formidable company going forward, with a strong balance sheet and capital base, attractive margins and good earnings momentum," said PacWest CEO Matt Wagner. So while CapitalSource is likely all popped out at this point, PacWest's newly boosted lending presence might be worth looking into.