Update - The first scan of the game can be seen below, showing that it already looks far better than the similar remake of Final Fantasy III [ Click to Enlarge]:

Plus the official website can now be seen here: http://www.square-enix.co.jp/ff4ds/
Stay tuned for more!
Original Story - Over a million sales of Final Fantasy III in Japan alone have seen great success of the series on the DS. In a rather unsurprising but more than welcome more, Square-Enix have announced that they are developing a full remake of the next entry in the series, Final Fantasy IV.
The title was unveiled in full in the latest issue of Jump magazine in Japan. Final Fantasy IV makes the move to full on 3D in what is sure to be another huge hit. It hasn't been made clear if the engine used in FFIII will be used in FFIV, but it has been confirmed that the same team will be working on the title.
On top of the visual overhaul, Square Enix also plan to include new episodes that will allow players to go more in-depth with the story-line than ever before. Needless to say, all the character designs and game style have been completely redone and updated for the title.
No release date has been set for FFIV, but more is expected from the Square Enix party this weekend. Stay tuned for updates.