One of Google’s biggest victories in terms of television advertising partnerships has unraveled.  Google and NBC Universal have dissolved the pact they established two years ago, meaning would-be advertisers will lose access to a number of high-profile channels.

Things got off to a promising start between Google and NBCU in late 2008.  The networks covered by the original deal included Chiller, CNBC, MSNBC, Oxygen, Sleuth, and SyFy (then Sci Fi), which seemed to indicate a fair amount of confidence on NBCU’s part.

But Steve McClellan reported today, "[S]ources said that NBCU had concluded that there was little value derived from having an Internet company sell its ads."

NBCU’s national sales teams are supposed to take over the operation, instead.

The good news for Google is that NBCU hasn’t cut all ties.  The company was able to say in a statement, "While we are no longer offering NBC Universal inventory through Google TV Ads, NBC Universal continues to be a great partner to Google. . . .  CNBC is an important partner in the launch of Google TV and we are working together on research studies."

It’ll just be interesting to see whether any other organizations follow NBCU’s lead, or if Google is able to find more partners to participate in its TV Ads program.