Major Nelson has tweeted that this week's Xbox Live Arcade titles will be Planets Under Attack and Warlords, to be released on the 14th November.
Warlords is the second time that the classic Atari 2600 game will be hitting XBLA. The first time was in 2008, and was a more faithful adaptation of the original game. The 2012 edition is more based in 3D graphics, but the goal is the same: demolish your opponents wall Breakout-style and destroy their castle.
Planets Under Attack, which was already released on Steam on the 27th September, is a bizarre tower defense / real-time strategy title in which players use planets and moons to fight off streams of invaders.