There are hints that Skype will be the default chat client for everything, presumably even game chat and regular voice communication on Xbox instead of just an add-on app to the service



From WPCentral:

We can file this one under “saw it coming from a mile away” but Computer and Video Games (CVG.com) has quoted an unnamed source who states Microsoft will be "consolidating all their communications technology" around the Skype platform. That includes the next generation Xbox, PCs, Tablets and in a way, even on our phones.

The move is of course far from shocking as Microsoft spent $8 billion to buy the famous VOIP company Skype for a reason. In fact, we’ve already started to see this happening with Microsoft collapsing MSN Messenger into Skype Chat, a process going on as we speak (except for China). Another recent example would be using your Microsoft Account for Skype logins.

  Microsoft reportedly putting Skype at center of communications for all devices and services