Comcast today reported fourth-quarter 2005 earnings that proved confusing more than anything. Overall, the cable giant saw a 69% drop in profits in the fourth quarter, but that was attributable to extraordinary investment income in the previous year and a change in tax status. Excluding that income and other extraordinary items, the company posted a profit of $186 million, or 9 cents per share--more than double the $91 million, or 4 cents per share, from the year-earlier period.

That seemingly good news was outweighed by market concerns that Comcast has yet to show much profit from its digital telephone deployment and is projecting only 10% to 11% cash flow growth for 2006 due to the costs of that deployment.

“These results are a big surprise. They are doing alright with the core business, meaning television and Internet, but voice phone service is very disappointing so far,” said industry analyst Jeffrey Kagan, in an e-mail post. “Comcast was the last cable television company to offer voice service during the last year, and everyone expected the results to be much better than they have reported.”

Cablevision, Cox Communications and Time-Warner Cable have all been more aggressive than Comcast in deploying voice services, largely using voice over IP, and marketing them as primary-line replacements.

But the Comcast numbers matched or exceeded many industry analysts’ expectations, as the company posted a revenue increase of greater than 9% to $5.7 billion.

Comcast added a net 40,000 basic video customers to end the year with 21.4 million customers, and added 378,000 high-speed Internet access customers to reach 8.5 million total. Digital telephony growth was slower, as Comcast added a net 79,000 new phone customers, to reach 1.3 million. That net figure includes a gain of 134,000 new customers and a shedding of 55,000 traditional customers from the circuit-switched business Comcast inherited in its acquisition of AT&T.