From the other point of view - Its only relatively recently that BT have been able to provide any content at all, and for the last few years Sky have been eating away at BT's core businees of phone /broadband supply.
The main way to survive now that BT can offer content is to nibble away at Sky's main business itself - ie Sports, and football especially. So to pay ~£300m per year (or £900m over 3 years), which to them is pocket change on the Billions of profit they make every year makes a lot of sense.
Forgotton what the program was called but this was said during the first 20 minutes or so of teh R5L program directly after 606 last night
As I cant get Sky where I live, Im quite glad BT have done this - I just hope my street gets fibre sometime soon, as Im stuck on an 8mb broadband line that usually maxes at under 2mb lol