Free-to-play titles could become a big focus for Sony in the coming generation.
In a recent interview at a media event, Sony Computer Entertainment CEO Andrew House says "We may well see free-to-play games on console be a much bigger factor...it will be a big part of the console landscape in this generation."
Certain developers are also interested in releasing free-to-play games, including Crytek who are changing their whole plan to support a free-to-play game business model. They are also releasing a free-to-play game for the PC called Warface, which you can read more about here.
CCP, developer of EVE Online also released Dust 514 last year, a free-to-play shooter MMO, exclusively for the PlayStation 3.
The PlayStation 4 releases on November 15th in North America for $399.