The Outlook for HDTV Comes into Sharp Focus

In the late 1990s, when the first television channels began offering high-definition television, few U.S. households had HDTV sets to receive the signals, and it’s no wonder: Shows in high-def were scarce, and the average price of an HDTV set was $3,147.

Now, as prices have plunged to as low as $500, and as most prime-time shows are now beamed in this format, the penetration of HDTV into America’s living rooms is approaching the tipping point.

In 2004, U.S. sales of HDTV sets grew by 78 percent, reaching.....