New rumors coming more frequently can only mean that things are heating up. VG24/7 has a report, saying that Microsoft has internally confirmed a holiday 2013 release, and have also released specs to all major studios (remember, some studios already have a spec kit). It will be powered in a configuration centering around a four, possibly six core CPU, and two GPUs that are in line with AMD's 7000 series. But they won't be set up in Crossfire, if you're familiar with running two AMD GPUs. They'll be running independently, allowing the CPU to utilize them independently for different processes. Basically allowing the XB3 to operate as two units as once, if need be.
It will have full Blu-Ray.
It will join the PS4 Orbis in needing to be connected to the internet 100% of the time. This is, unfortunately, the future of gaming. Many PC titles already do it, Sony looks to be doing it with Orbis, and Project Durango joins the pack. It makes sense from their side, as the 360 was a huge target of pirating for a long time. Always connected use means there's no chance for someone to flash their unit and run pirated ROMs.
Much of this info has leaked from a Project Durango summit that happened in London at the end of February. But even though studios know exactly what they're developing for now, it still looks like Microsoft plans to keep all info until calendar 2013. So even though we know a lot of details via rumors, there will be no public info at E3, or PAX, or Gamescom, or anything else this year. But, given the timeline of a Holiday 2013 release, I'd be shocked if they waited until the big expos in 2013 to announce. My guess is they follow a similar timeline of the 360, which would have them doing their own press announcement before the summer Expo schedule. Maybe March or so.
And all this means is that I will 100% be buying tickets to PAX East in 2013.