According to PS3.IGN, Sega RPG Valkyria Chronicles has an optional HD install designed to cut down loading times. From the piece:
The install takes up 3,336 MB and apparently cuts down load times from the 15 second waits players would otherwise have to sit through when opting to play directly from disc.
As with last month's Ryu ga Gotoku Kenzan install, this install is strictly optional, so those who can't find enough space on their hard disk will still be able to play.
The PS3 exclusive will be launching in Europe later this year.