Just over a month ago a Resistance 3 PS3 billboard ad was spotted in Louisiana.
Today, adding more credence that a third game is in development comes a listing in Ben Mauro's http://www.linkedin.com/in/benmauro which confirms his involvement with Resistance 3 among other projects.
To quote from GameGuru.in (linked above): "The first instance of resurgence of Resistance 3 was in the form of a billboard for a movie that was due sometime next year.
Then came the quote about Killzone 3 and Resistance 3 being rumored to be in projects, is in development by Insomniac Games.
This discovery comes from Ben Mauro's LinkedIn profile who has worked on the project for three months in 2009 along with the latest iteration of the Ratchet and Clank series."
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