[sp332]

The OS understands twitter and facebook natively. If I message someone on facebook, I see that conversation right in-line with my SMS chats with that contact. So there's just one tile for all my messages.

There is a single "People" tile that shows me all the news from facebook and twitter in a single stream. There is another "Me" tile that shows my notifications about mentions or tags.

I think the most important thing is that tapping these doesn't feel like launching an app. I don't have to "go check facebook" and wait for it to load, and then "go look at twitter," etc. I just tap a tile, and in 4 seconds I have everything in one native-looking interface - it even honors the color scheme I picked for the phone :)