If you were previously given access to one of the Rainbow Six Siege [official site] closed betas, you can now preload the game's final beta and start playing later today. If you've not previously had access, then no matter: the beta will explode open its doors to everyone tomorrow and run for all through till Sunday.
The beta lets you select from 14 operators, where operators are the different kinds of class loadouts you can play as, then play on three maps (Kanal, Hereford, House) across three game modes (5vs5, Bomb, Secure Area). We've seen most of this in previous betas, and given the proximity to the game's full release on December 1st, it seems a little like a demo. Except time limited. So like a demo but worse.
Meanwhile, Rainbow Six Siege seems pretty darn great based on my experience playing it in previous betas. It's a modern military shooter but at its core is tech that lets you destroy the scenery, such as blowing holes in walls to create new entrances. It's like the future Red Faction promised us in 2001. This also means that its battles are asymmetric, in which defenders place traps and reinforce walls then hunker down to deal with an invading enemy attempting to breach and clear. It puts the focus on tactical positioning and level awareness, which are things I like in my first-person shooters.
And also it lets you blow things up and rappel down buildings.
I have no idea if anyone wants a game like this, but it is, in some sense, trying to be the game I wanted while playing cs_militia and cs_assault in Counter-Strike for years and years and years. The beta can be pre-loaded now by those who have access through UPlay now, by going to your 'Free Games' tab within the client.