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In aiming for some of the highest-level quality NEOGEO emulation seen on PSN yet, coupled with a set of online features for PlayStation gamers, we look forward to releasing the most highly revered title in the Metal Slug series together with PlayStation in the coming months.
We'd like to take this opportunity to thank our fans for their hunger for more content on PlayStation, and kind patience as well.
More details in regards to specific game features will be announced in the coming months.
http://blog.us.playstation.com/2014/08/28/metal-slug-3-coming-to-ps4-ps3-ps-vita-this-winter/