In the eyes of telecommunications and satellite TV providers, Comcast Corp. (CMCSK, CMCSA) could make an awkward transition from heated rival to a major content provider, if the Philadelphia company succeeds in buying a stake in NBC Universal.

The reported talks between Comcast and NBC parent General Electric Co. (GE) are still in the early stages, but any potential deal drastically changes the competitive dynamics. Rather than fighting for the best programming rates from NBC Universal properties, Comcast will be on the other side of the bargaining table striking deals with distribution competitors such as AT&T Inc. (T) or DirecTV Group Inc. (DTV)

It's unclear what, if any, changes will come if Comcast has a hand in the creation and sale of NBC content. The company already runs several niche cable channels, notably E! and the Golf Channel, and has to follow existing program-sharing rules. Any deal would fall under intense regulatory scrutiny.

"Given the magnitude of a Comcast-NBCU deal ... we would not be surprised to see other pay-TV operators considering asking the (Federal Communications Commission) for a more effective enforcement process," said Paul Gallant, analyst at Washington Research Group.

There is no shortage of friction between the cable providers and its telco and satellite TV rivals. The rhetoric between the cable and telcos is particularly vehement because both compete directly on television and phone services.

AT&T and Verizon Communications Inc. (VZ), for example, have complained to the FCC that Cablevision Systems Corp. (CVC) is wrongfully withholding high-definition sports programming from the telcos, although they can access the standard-definition version.

AT&T has a similar complaint regarding Cox Communications' exclusive rights to broadcast San Diego Padres games. The FCC has yet to make a formal ruling on either of the complaints, although its media bureau panel has advised dismissing AT&T's complaint.

Comcast, despite a harsh advertising campaign against its rivals, has kept a generally cordial relationship in regard to its programming deals.

"We've been able to live with its past practices," said Verizon spokesman Eric Rabe. "They have not made a big fuss."

A deal would bring few changes to the programming deals, according to industry observers.

"It tilts things slightly, but not in a significant way," said Thomas Eagan, analyst at Collins Stewart.

AT&T and DirecTV declined to comment. A Dish Network Corp. (DISH) spokeswoman couldn't be reached for comment.

Cable operators Time Warner Cable Inc. (TWC), Cablevision and Cox, which would also have to potentially deal with Comcast, declined to comment.

Time Warner Cable could be seen as a warning to Comcast: The company spun out of Time Warner Inc. (TWX) because it couldn't find adequate benefits from operating as one combined entity.

Verizon shares fell 0.2% to $29.95, while AT&T slipped 0.4% to $26.50. DirecTV fell 1.1% to $27.19 and Dish fell 0.6% to $19.25.

The cable companies fell more significantly, possibly on fears that other cable companies may need to follow Comcast's lead with a significant purchase of content assets. However, Gabelli & Co. analyst Christopher Marangi argued that any move by Comcast to shape the digital future of television in its favor could benefit the entire industry.

On Friday, Comcast shares fell 3.6% to $14.39, Time Warner Cable slid 3.3% to $40.38 and Cablevision dropped 2% to $22.54.

Regardless, most players are taking a wait-and-see approach.

"We're watching it, but no one's obsessing about it here," Verizon's Rabe said.

-By Roger Cheng, Dow Jones Newswires; 212-416-2153; roger.cheng@dowjones.com