Microsoft and the NFL announced a partnership over the summer as part of the big Xbox One reveal. The partnership was to provide content to Microsoft's next generation entertainment platform.
Microsoft has now confirmed that the ESPN App will be coming to the Xbox One. In addition, David Jurenka, Director of Sports for Xbox Entertainment Studios, would also like to have the Yahoo and ESPN fantasy football available sometime in 2014.
Engadget article by Dana Wollman here.