Just thought I'd update this topic by saying the 5th AA has its name in English: Phoenix Wright: Ace Attorney: Dual Destinies
It will be available fall 2013 ONLY for the 3DS eshop.
(I don't think the following counts as spoilers, so I'll continue)
Main characters Wright and Apollo Justice will be playable. The new assistant is named Athena Cykes. (Apollo and Athena...get it? aha...ha...)
It's a little disappointing that the game can't be bought physically at a store and will probably hurt its sales.
But other than that, the trailer (http://www.youtube.com/watch?v=XAPlAzB38uU
) looks pretty cool. Can't wait. I'm downloading it the first day.
What do you think?