If you've been holding off on switching to a Windows Phone until it gets a few features, here's an interesting rumour for you chew on: WMPowerUser says that Microsoft is working on a new group chat feature that apparently works in a similar fashion to BlackBerry Instant Messenger and Apple's iMessage.
WMPowerUser says it discovered the new feature, called Room, in some code nestled deep in the Windows Phone 8 SDK. It describes the service as such:
Gather your friends and family together. Invite them to a private Room where you can share a calendar, photos, group chat and notes. Or add them to a Group to see social updates from just those folks and text them all at once. Tap the plus sign to get started.