Sony used this year's CES event to drop a couple of pieces of news: firstly, that the PS4 sold 4.2 million units by the end of 2013 and secondly, that their new Gaikai-based streaming service, Playstation Now, will be available in the US this summer.
There's no news on whether or not Playstation Now will be included with Playstation Plus, or if PS Now will affect the range of games available on PS Plus. Sony have announced that users will be able to rent specific games if you don't fancy a subscription-based account.