What a difference a recession makes.

Eight months ago, Boeing's (NYSE:BA) biggest bogeyman was its fear that a machinists' union strike would delay production of the firm's 3,400-plane backlog of work to be done. Its second biggest worry was that such delays would invoke penalties for late delivery of the planes. Customers like Continental (NYSE:CAL),Delta (NYSE:DAL), and AIG's (NYSE:AIG) International Lease Finance subsidiary were queuing up and clamoring for their planes, and Boeing was already hip-deep in problems producing them.

Only two problems? We should be so lucky
On Friday, a third and more serious concern became actual, as Boeing revealed that instead of making it pay up, customers are backing out (of their contracts). An "unidentified" customer canceled a $4.44 billion contract to purchase 25 Boeing 787s, which when combined with other cancellations announced earlier means that Boeing has now lost more sales than it's inked so far this year -- 59 cancellations versus 58 new orders.

Who pushed Boeing over the brink? Well, Delta was said to be considering nixing a flight of 18 787-8s that it had on order. Last I heard, AMR's (NYSE:AMR) American Airlines was still debating its optional purchase rights on 58 additional 787s—but if cancelled, those wouldn't be firm orders.

My best guess is that Continental's the culprit. We know the company had a 25-plane detachment that included at least 17 of the 787-9 variant on order. A little calculator work tells us that the 787s that got canceled last week were of this very variety. (The per-plane sales price, after presumed discounts, comes to just under $180 million apiece – just a bit south of the 787-9 sales prices according to Boeing's price list.) Put two and two together, and I think it equals: Continental.

What's it mean to investors?
Depends on who you invested in. If Continental, then last week's news suggests business is bad. The first 787-9 isn't even expected to enter service until 2013. Whoever's canceling 787-9s today -- whether Continental or someone else -- thinks the airline business is pretty rough. (In which case, someone should inform Priceline.com (NASDAQ:PCLN). With first-quarter profits up 89%, they apparently didn't get the memo.)

But if you own Boeing, I see two implications. You know the firm's "$350 billion backlog"? It seems that number is -- ahem -- up in the air. But by the same token, don't lose faith entirely. Backlog is never set entirely in stone, and orders that vanish into thin air today can return out of the blue if and when the economy turns back up.

Hope, as they say, springs eternal.

For more on Boeing, read:

Fool contributor Rich Smith owns shares of Boeing and Priceline.com. Priceline.com is also a Motley Fool Stock Advisor recommendation.

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