It was just a matter of time.

In the latest evolutionary step in online-marketing domination, Google (NASDAQ:GOOG) will now begin canvassing the Web with contextual ads on third-party videos.

Sure, Google was slow to monetize its YouTube monster. YouTube didn't start inserting overlay ads onto its clips until this past summer, and even then, it limited itself to revenue-sharing deals with its largest content creators.

Google never has to be the first mover to be the top dog. Sites such as Revver and Metacafe have been paying all of their original video makers -- not just the top draws -- for a couple of years now. Sites such as VideoEgg and Revver were popping ads into their videos long before YouTube dived in. Even this morning's move to insert ads into third-party videos isn't original. Video-search specialist Blinkx (OTC BB: BLNKF.PK) has been offering something similar since last year.   

Initial partners in the Google AdSense for Video program include video content platforms such as Revver, YuMe, and Brightcove, as well as actual content producers such as More are sure to come.

By allowing text-ad inserts -- not just the graphical video ads that are more common -- Google opens up the advertising platform to even the smallest of sponsors. Anyone can peck out a few words of promotional copy, and no one has a thicker list of advertisers than Google does.

Rivals don't shed tears when Google arrives late to the party. They just chew their fingernails down to the bone. Just ask Yahoo! (NASDAQ:YHOO). It had the inside track in paid search when it acquired Overture five years ago. Google subsequently launched its AdWords program and is now the undisputed champ of targeted text-based advertising.

Whether it's Microsoft (NASDAQ:MSFT) with productivity software or Adobe (NASDAQ:ADBE) with presentation software, if there's a way to deliver apps through Web-stored solutions, Google is going to crash the party.

Competitors don't have to leave the party when Google arrives. They simply have to concede the baton that belongs to the life of the party.    

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