Although Twitter Promoted Tweets Come To Google, according to SearchEngine Land (November 3, 2010), they will not be displayed as part of results returned by regular Google search.
How WILL it work?
SearchEngine Land emphasized that Promoted Tweets should be thought of in the context of real-time information.
… regular Google search… sometimes integrates real-time matches along with web search listings and other matches.
[However] they [the Promoted Tweets] will only appear when someone drills-down into the real-time results after doing a regular search at Google, or if they conduct a search from the still relatively new Google Realtime Search home page.
Note the precedent here: this is the FIRST time Google has carried ads directly from someone else’s advertising network, via a Google search product, and not through Google’s AdWords system.
The Promoted Tweets will be displayed first, before all other results returned by Google Realtime Search queries.
What benefit does Google derive from this?
Twitter and Google will split revenue 50/ 50. Twitter has stated that its advertising partners would share equally in Promoted Tweet advertising revenue in the past.