Only 2 of the 4 games mentioned in that leak were at the press conference, so I wouldn't trust much else that it has to say.
As for the press conference itself, it's definitely the best Xbox conference in years. Lots of games, only a little bit of Smartglass crap, and an utterly pointless ad for McLaren, but overall it was good. However, as a potential buyer, the games that really intrigued me most appear to be multi-platform, none of the exclusives would convince me to buy this over the PS4. It just wasn't enough to overcome all the reservations I have with the DRM.
The price is expensive, and I expect the PS4 to undercut them with a $400 console.
This will never happen. If the brain(dead)trust at Microsoft pull something like this for all games and XBone models, it will literally mean the death of the Xbox.
After seeing the press conference, I'm now guessing that this rumour only applies to the free games that MS are offering to Gold subscribers. If you have Gold and download Halo 3 for free, then you wont be able to play it if your subscription lapses. This is the way that free games on PS+ works.