It appears that Microsoft's decided to follow up on one of Valve Corporation's previous ideas, much to the benefit of the Xbox 360 owners. MS has announced at the E3 2008 that Portal: Still Alive is being readied as an Xbox Live Arcade (XBLA) downloadable for this year.

Still Alive will carry the Orange Box's Portal game plus a new challenge mode. No other details were shared at the moment, though we imagine this news is more than enough reason to celebrate for the fans.

Other games expected to arrive in XBLA for this year are Galaga Legions, Geometry Wars: Retro Evolved 2, and UNO Rush. Namco Bandai's Galaga Legions in particular should be familiar to the fans of the original Galaga from 1981, with the XBLA release promising new game dynamics, and vastly enhanced visuals.

Bizarre Creations' Geometry Wars: Retro Evolved 2 will be coming this year with six new gameplay modes, new enemies, and new scoring strategies. Microsoft's Uno Rush is a sequel to the XBLA's Uno title, and will feature full avatar, LIVE Party Chat, Xbox LIVE Vision camera, and Big Button Pad support. A new South Park game has also been announced for XBLA for 2009, although no further details have been released.

There's also the planned XBLA release of the original Banjo-Kazooie title along with its Stop ’N’ Swop feature, which should do well to complement the arrival of Banjo-Kazooie: Nuts & Bolts. Lastly, Microsoft has revealed that Fable 2's anticipated Pub Games collection of mini-games will be arriving this August.