Currently, it’s got the basic functionality of things you’d want to do away from your Xbox, like check/send messages, achievements, and friend activity. You can even check out some streaming video content from the Xbox LIVE team. You can’t, however, browse the Xbox LIVE Marketplace and make downloads or purchases. This would be the logical next feature add and I’d be surprised if Microsoft didn’t implement this sooner rather than later. After all, allowing players to impulse purchase content on the go can only do good things for Microsoft’s bottom line.
Here’s a list of features from Major Nelson:
Some of the features include:
Read and send messages to friends
Manage your friends list, invite new friends
Read and Edit your full LIVE profile (name, bio, motto)
Change your avatar features/items with the avatar closet
View and compare your achievement progress with friends