The next Xbox (Durango, Infinity, 720) might be delayed because Sony has an exclusive license for the console market. This rumor comes from the website Mondbox which received the information from a source working in a large Italian commercial chain.
Apparently there is a clause in the Blu-ray licensing terms that gives Sony the exclusive rights to implement Blu-ray in game consoles. Sony's Playstation 3 console supports Blu-ray, while the Xbox 360 lacks support for it.
Microsoft did release an external drive supporting the competing HD-DVD format but this never got popular and has been vanished. Sony's support for Blu-ray is no surprise since it's one of the initiators of the format and both the Playstation 3 and Blu-ray have been positively influencing each others popularity. Since Sony is heavily involved in Blu-ray it is a possibility that the company has exclusive rights to support it in game consoles.
So far it's unclear if the release of the Xbox will only be delayed in Europe or that it will be a global issue. It's also still unsure if the Xbox will actually have a Blu-ray drive or that Microsoft will decide to use a proprietary format like Nintendo implemented on the Wii U. A proprietary format could be used as a way of reducing of piracy, however the past has proofed that while it makes piracy more difficult it doesn't actually stop it.
The next generation Xbox console will likely be announced on the 21st of May this year and was expected to launch during the holiday season. However Microsoft might miss this sales opportunity and launch long after the Playstation 4 becomes available. Sony's upcoming next generation console in on schedule to release the holiday season of 2013. The new Xbox might not become available earlier than the first quarter of 2014.
