The Last Remnant, most notable for being Square's first project using Unreal Engine 3, is an RPG that will be released on both PS3 and 360. It will be simultaneously released in North America and Japan later this year.
Star Ocean: The Last Hope is the fourth main Star Ocean title, and an exclusive for the Xbox 360. The previous Star Ocean titles appeared on Super Famicom, Playstation, GameBoy Color, and Playstation 2; which makes the Xbox exclusivity a bit odd in my opinion.
The last (get it?) new title shown off by Square Enix is a completely new franchise being developed by tri-Ace (the same developers behind Star Ocean). Infinite Undiscovery is also an RPG.
From the looks of it Microsoft really wants to start selling Xbox 36o's in the Eastern market, and Square Enix is more than willing to help. Perhaps the reason behind these being Xbox 360 exclusive is the fact that Sony is getting the entire Final Fantasy XIII catalog. Also note, Square has yet to release any title on the Playstation 3...