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 AMR (NYSE: AMR), parent of bankrupt American Airlines, soared as much as 28% in early trading but gave up most of that gain by the closing bell. The stock finished up 3%.

So what: While analysts are touting the opportunity AMR's bankruptcy represents for peers US Airways (NYSE: LCC), Delta (NYSE: DAL), and United Continental (NYSE: UAL), investors were encouraged by American's initial cost-saving moves -- including a plan to surrender 24 shorter-haul aircraft to save on leases and storage.

Now what: American also plans to shed leases for space at Chicago's Midway airport and a base station in Kansas City, Mo., Reuters reported. Smart. Both American and United already call Chicago's O'Hare a hub, which makes Midway overflow. Yet I'm also not sure it matters. AMR's bankruptcy is likely to cancel the shares -- any play on them now is a sure loser unless you're buying to flip. Do you agree? Did you buy today? Please weigh in using the comments box below.

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