In a move that would make one of nation’s major television networks the owner of top-10 Internet company, CBS said today that it’s buying media firm CNet Networks for about $1.8 billion.

 

At $11.50 per share, the deal represents a 40 percent premium over San Francisco-based CNet’s Wednesday closing price of $7.95.

 

CNet includes a network of technology- and entertainment-focused Web sites.

 

CBS Chief Executive Les Moonves described the new acquisition as a “profitable, growing, well-managed Internet company.”

 

“Together, CBS and CNet Networks will have significant additional exposure to the fastest- growing advertising sector and can accelerate our growth through a number of new content, promotion and advertising initiatives,” Moonves said in a written statement.

 

Officials say the deal could be completed as early as the third quarter.

 

Once that’s done, analysts say, the broadcasting giant’s digital properties will represent 54 million unique monthly users in the United States and about 200 million users worldwide.

 

In a conference call today, Moonves said, “When you can combine the entertainment assets, the news assets, the platforms that are available with technology, the cross advertising opportunities, it just gives us great scale.”

 

CBS said it expects CNET and its own so-called “Interactive” unit together to reach $1 billion in revenue within three years.

 

Moonves said the deal would be funded from excess cash on his company’s balance sheet and would not affect CBS’s dividend, according to news reports.

 

CNET’s network of Internet sites including ZDNet, GameSpot.com, TV.com, and UrbanBaby.com. The company posted $406 million in revenue in 2007.

 

The group last month reported that first-quarter net losses narrowed to $6.1 million, from $9.1 million one year ago. A 3 percent rise in revenues to $91.4 million missed Wall Street expectations of $100 to $104 million for the second quarter.

 

Shares in CBS fell 2 cents to $24.80 in premarket trading.