Recs.
Updated
Sector's Edge is a fast-paced first person shooter for Windows, available on Steam this July. Two teams of 8 fight for zone-domination across different planets in completely destructible environments.
SpecsUpdate
Pros
Pro Full destructible and build-able environment
Being a voxel based game, the world is composed entirely of blocks which are all individually destructible. By the end of a standard game, the world you started in will look completely different due to the destruction and chaos that takes place during the course of the game. You can also build anything you like, from a bridge to a wall, even to a small base if you want.
Pro Great visuals
It's obvious the developers have poured a long time into developing the core game engine - there are many variants of blocks unique to each map, it has great texture detail, models, lighting, and the skyboxes are terrific.
For a voxel game like this, it's potentially the prettiest.