Cable shares were beginning to get back on track. FCC plans to further regulate the industry never made it off the ground. It looked like the the industry had clear running.

But, Comcast (NASDAQ: CMCSA) issued a profit warning saying that its cash flow in 2007 might be only 80% of what it was last year. The number of subscribers it expected to sign up would fall from previous forecasts and capital spending on new infrastructure would rise. Barron's reports "the company now sees revenue generating units up about 6 million, to 57 million, rather than previous guidance of 6.5 million unit growth. Comcast now sees cable revenue growth of about 11%, down from previous guidance of at least 12%."

It appears that Wall Street was right when it began to fear the worst about fiber-to-the-home competition from telephone companies. The new technology allows them to offer fast broadband, HDTV, and voice service in one package. For several years only cable could do that. Now the telecoms, lead by Verizon (NYSE: VZ), are aggressively offering their own packages.

For investors, the problem is that new competition is likely to keep cable stocks down for a long time. That means that the lows that they hit recently may be as good as it gets.

Douglas A. McIntyre is an editor at 247wallst.com.