NEW YORK (Reuters) - Comcast Corp struck a deal to buy a majority stake in NBC Universal from General Electric Co, creating a media superpower that would control not just how television shows and movies are made, but how they are delivered to the home.

The deal had been discussed for months and brought to light deep divisions over the future of the media business, with some lauding Comcast chief executive officer Brian Roberts as a visionary and others calling it the most foolhardy acquisition since AOL bought Time Warner in 2001.

In a world where the Internet has disrupted traditional media, Comcast wants NBC Universal so it can deliver programming to audiences however they may want it — whether through TV sets, personal computers or mobile devices. Not only is Comcast the largest US cable distributor, it also is the leading Internet service provider to homes.

Critics of the deal, including some of Comcast's own shareholders, suggest there is too little overlap between the businesses to draw out meaningful savings, and that competition regulators are bound to burden it with restrictions.

Moreover, big media deals rarely work, they say, pointing to Time Warner Inc's breakup as an example. Once the world's biggest media company, Time Warner has spun off Time Warner Cable Inc and will soon do the same with AOL.

"There's no question that you really have a great little test tube here because you have one large company that said this is absolutely not the thing to do," said veteran media dealmaker Barry Diller, CEO of IAC/InterActive Corp.

"And you have another company that said it's exactly the thing to do," he told the Reuters Global Media Summit. "So it's going to be an interesting comparison over time."

Comcast's shares have fallen 11 percent since reports of the deal talks first surfaced in September. The stock was up 6.5 percent at $15.91 yesterday, after Comcast unveiled the transaction and raised its dividend 40 percent — a move analysts said was aimed at appeasing shareholders. GE's shares rose nearly one percent.

"We're still very unsure about the value created from this deal," said Collins Stewart analyst Thomas Eagan.

"They definitely heard concerns on Wall Street over the past couple of weeks about the deal inhibiting their ability to buy back shares or increase their dividends," he said.

The deal calls for Comcast to contribute $6.5 billion in cash, its own cable TV networks and other assets in return for a 51 percent stake in NBC Universal, owner of TV networks, a movie studio and theme parks. GE will keep a 49 percent stake.

The companies said NBC Universal's businesses have been valued at $30 billion. The Comcast businesses that will be part of the deal — including E!, Versus, the Golf Channel and 10 regional sports networks — are valued at $7.25 billion.

The deal culminates negotiations that began last spring, nearly collapsed several times along the way, and were kept secret from even top-level NBC Universal executives until September, when news reports of the talks surfaced.

GE also had to secure Vivendi SA's agreement to sell its 20 percent stake in NBC Universal for $5.8 billion. That was in doubt until GE CEO Jeff Immelt jetted to Paris for a sit-down with Vivendi, after attending a state dinner hosted by President Barack Obama. Immelt, who for years showed no public interest in selling NBC Universal, only began seriously considering a deal with Comcast after a March breakfast meeting with JPMorgan banker James Lee, according to a source close to the talks.