Bioshock Infinite - $39.99
Tomb Raider - $19.99
XCom Enemy Unknown - $19.99
Gears of War Judgement - $29.99
Hitman Absolution - $9.99
Metal Gear Rising Revengeance - $29.99
Currently priced on Xbox Live, looks to be the remaining on the list.
Only one I am not 100% sure on if there actually was a price change was Metal Gear.