1. Relatively easy to develop, powerful machine. This meant they could release early and better still get the incredible content like Oblivion 6 months out from release, Gears of War 12 months out and Halo 3 22 months out from launch and continually get 'free' exclusives like the powerful Left 4 Dead franchise which has sold better than Sony's recent shooters. In addition to this, because the machine is so well balanced it made a more powerful machine on paper look weak by comparison in multiplatform games, so it stole the one thing Sony paid a lot of money to get, their performance advantage.
2. Early launch. They got a decent start and it wasn't that many sold but it enabled them to be the early primary system for development and to set the tone of the entire generation. It enabled them to get a head start with the important online, shooter, and western RPG markets.
3. Xbox Live. Its simply the best online service, arguably anywhere though I will stick to consoles here. It took PSN a long time to even catch up to Xbox Lives launch features and in the meantime Microsoft gained a large online audience, especially the hardcore online players. Being able to play with your friends has been the shield which has kept the PS3 at bay in the U.S.
4. Hardware price. Hey it was cheaper, and that was when there was little HDTV adoption or content to justify Blu Ray on the PS3. Good call Microsoft. It didn't make people buy Xbox 360 when they saw the PS3 was too expensive, Gears of War did that. It simply opened the choice up to people who were disapointed with the launch price of the PS3.
5. Gears of War/Oblivion/Year one lineup. They had some pretty awesome games in Gears of War 1, Oblivion etc. These were the games which made the Xbox 360 a viable alternative to the PS3 at launch. People could have waited, stretched to buy a PS3 at launch with few games or a cheaper Xbox 360 with two-three awesome games. A lot chose the 360 and thats important to note.
6. Halo 3, Goes without saying why really.
7. PC/360 port friendliness. In the age of the multiplatform its more important that your system can easily port between architectures. In this case its given them a lot of free exclusives they would have otherwise not got. It also allowed developers to be swayed by a timed exclusive PC/360 with the port coming to the PS3 later.
8. Financial strength of Microsoft. It let them try a lot of things like in Japan and support a lot of development which may/may not have come off. It also allowed them to continually advertise their system without worry. I believe the PS3 went almost a year without a decent advertisement campaign for example.
9. Luck, yes they've had some. The Wii wasn't a core gamer monster like predicted and the PS3 was a foot in mouth disaster from a PR perspetive and more which I won't list.
10. Persistance. Good things come to those who try and they did try so very hard. They were also the most forward looking company in terms of the development climate and the nature of the current port everything mindset.
Do you know what its like to live on the far side of Uranus?
