(1) Will the game also be purchasable through Steam? I have gone to Steam and it doesn't seem that the game's page was updated saying that the release date is still March 31st.
- Yes, you will be able to purchase the game through Steam, surely it will update in the next few hours.
(2) Will I be able to save the 10% off through Steam as well if I purchase the game within the two weekd of its release?
- Steam being the official launcher of the game, certainly you will be able to save 10% off on Mount&Blade II Bannerlord.
(3) Will I be able to use my Warband CD-key through Steam to get an additional 10% off?
- That answer for that question is unkown atm, but I believe so. If not you should get 20% off if you buy Mount&Blade II Bannerlord from the website (TW store) also you support more TaleWorlds Entertainment because Steam gets (30% cut), you just need to have atleast one game registered on your TaleWorlds website (account).
You can buy the game on TaleWorlds website and you will recieve a key to activate the product on Steam.
Hope this info helped you out.