Pachube blog: As far as Google PowerMeter, we'll carry the torch from here! We already have almost 10,000 users who are managing their personal energy data on our platform. Users will find graphing tools, dashboards, mobile apps, and embeddable widgets in our app repository that can be used with any real-time data, including energy data. Moving forward, we are working with application developers and hardware companies who are building energy-management products to connect into Pachube and are always on the lookout for more. Additionally, disaffected PowerMeter users can bring their historical data into Pachube by using our import app. To get data pushing directly to Pachube in real-time moving forward, we will need to work with the data provider or hardware manufacturer. Users should let them know they want to get their data into Pachube and then have them contact us at email@example.com. We'll take it from there. Also, we're happy to extend free Premium accounts to users who bring their data over from PowerMeter.
Current Cost is not fully integrated. They say they are working on it - see comments on the blog above. In the meantime there is an app available for that purpose. See the categories for more cool stuff.
Pachube also give an opinion on why GPM failed: Closed eco-system.
Pachube Premium: Private and public feeds, Unlimited historical storage, 250 datastreams, Import unlimited existing datapoints, 250 API requests minute