Ubisoft is doing a closed alpha for the upcoming Rainbow Six Siege, and you can sign up for it now.
There is a bunch of questions and answers in this FAQ, but the main things you should know are that it's North America and Europe only, PC only, and English only. You also need to make a Uplay account to sign up for the alpha.
They also gave the system requirements, but these are only for the alpha and not for the full release:
|OS:||Windows 7 x64, Windows 8 x64, Windows 8.1 x64|
|CPU:||Intel Core i5-2500K||AMD FX-8120 Eight-Core|
|Clock speed: 3.3 GHz||Clock speed: 2.6 GHz|
|Cores: 4||Cores: 8|
|Launch date: Q4 2010||Launch date: Q4 2011|
|*CPU score: 6479||*CPU score: 6591|
|GPU:||Nvidia GeForce GTX 670||AMD Radeon HD 7970 / R9 280X|
|Launch date: Q2 2012||Launch date: Q1 2012|
|*GPU score: 5380||*GPU score: 5171|
Siege is something that intrigues me. I'm a huge Rainbow Six fan, but this game simply doesn't sound appealing. The idea of having a match centered in a house seems very limiting, but I'm sure Ubisoft wouldn't have done it if they didn't think it would be exciting.