According to the latest Famitsu Magazine, R-Type 3D is coming exclusively to the PS3 console.
It appears that R-Type Final is indeed not the last in the series, according to
distantmantra commenting on the latest Famitsu issue at http://www.neogaf.com/forum/showpost.php?p=18236208&postcount=850: "There's something about a PS3 exclusive (?) R-Type 3D, and 3D Dot Game Heroes got 8/8/7/7."
For those unaware, R-Type is a side scrolling shoot-em-up arcade game produced by Irem. The player controls a space fighter named "Arrowhead" to defend humanity against a mysterious but powerful alien life-form known as "Bydo", which was later discovered to be not entirely alien in origin.
To quote from Examiner.com (linked above): "It is unknown whether the "3D" in title means that the game will take place in a 3D plane or whether it would be in a 2D plane with 3D graphics (a la R-Type Delta)."
More details to come as they are available!
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