Google acquired Jaiku, a Helsinki-based continuous partial presence startup. I'm really happy for Jyri and the whole Jaiku team.
My best post about Jaiku is here. Google just got one of the better mobility and social software design teams. They have a far richer understanding of presence than anyone I've met. It seemed when they got started that they would be bought by Nokia, who is trying to turn into an internet company. Jaiku is more than a Twitter alternative. With Google's portfolio, you could easily see it augmenting Gtalk and Orkut on the web and mobile clients.
But perhaps the greatest direction they can go with this is lifestreaming. Follow me on this. Google has said they will compete with Facebook through openness. Facebook's Social News Feed is the new Inbox, the focus of attention when it is the economy. To compete against it, the challenge will be overcoming the semantic advantages Facebook has by keeping everything on their platform for constructing the Social News Feed. With Google's savvy around structuring the unstructured, picture lifestreaming evolving into something that infers permalinks for social activity. One day your Google homepage may be a stream of your friends and what they are doing, sharing, and adopting.
Then again, Anil might be right that Jaiku is the new Dodgeball.