I played the demo, but not finished yet. The game will be out in September, using an enhanced version of the UT engine from a 3rd person perspective.
In the demo you play Captain Sisco, starting aon a planet looking for federation emergency pods that went down there.
It looks really good, music is gorgeous, 3D sound well done. Only letdown: no saves except autosaves, and no voiceovers (at least for me), only subtitles.
You can get it from http://www.ds9thefallen.com (92 MB), also a patch (86k, just changes DS9.ini), and a D3DDrv.dll to improve performance with non Voodoo chipsets.