The U.S. Oil Fund (AMEX: USO) held up last week But Exxon Mobil (NYSE: XOM) broke below key support.

So the big question is whether Exxon's break is signaling an upcoming break in the price of crude oil, or if the selling is just due to Exxon being liquid.

Lots of hedge funds and big private equity firms have reportedly been getting margin calls, and at least some of them have not been able to meet them.

That suggests that last week's selling was more due to margin calls than anything else, despite the overall bad economic news.

Still, the traditional view is that weak oil stocks will eventually forecast weak oil prices.

This traditional view has not held up too well lately. That means that for now, we hold on to USO.

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