It is hard to believe that the nation’s largest retailer could do much to hurt a satellite radio company. But, think again.

Wal-Mart (WMT) is going to be selling high-definition radios. As The Wall Street Journal points out the "radio industry is positioning HD radio as a free alternative to satellite radio".

Of course, without a big sales channel for high-definition receivers, the regular old radio guys would have trouble going after Sirius (SIRI) and XM (XMSR). That is where Wal-Mart comes in. The retailer even describes HD radios as something of a second coming:  "We want to offer incredible products at a great value; this is a perfect example."

Satellite radio already had enough problems.

Douglas A. McIntyre