A few days ago T-Mobile in the USA went live with Bobsled, a VoIP service that ties into Facebook accounts for what I like to call Social Calling. Now out of the UK we have Telefonica's operating brand, O2, going live with a service, not that different from their parent's VOYP service offering. I think this will be a trend as operators begin to realize just how much they have been losing to Skype.
I'm also guessing that the new O2 sevice is new, as it appears freshly minted, and in the abscence of any refererence to the Jajah or FonYou services that Telefonica is using in other parts of the world that this is likely something new that their UK team cooked up.