I would say that after the Paramount deal, the studio releases this fall were pretty even. So, it's not correct to say that content was what decided the war, since it was practically a stalemate. Universal and Warner going all out for HD-DVD, and then Paramount switched and released the biggest movie of the year.
The Playstation 3 is the only reason Blu-Ray won this entire thing. Without the Playstation 3, 300 wouldn't have outsold the HD-DVD version 2:1. Without the Playstation 3, Blu-Ray would have never recovered from their initial and terrible entry into the market, where HD-DVD had an advantage from the start. HD-DVD already had a pretty good pricing advantage, and the average consumer doesn't care about tech specs. So, ironically, it wasn't software that won it this time, it was hardware. The PS3 was a trojan horse and it worked.
And given all that Sony's invested into the machine, they damn well deserve to win.