Soulcalibur: Lost Swords has been revealed as a free-to-play PlayStation 3 exclusive.
Soulcalibur: Lost Swords will presumably utilise a similar model to Tekken Revolution, which released additional characters over time.
There's no confirmation of a Western release just yet but, seeing as Namco Bandai trademarked Lost Swords in North America a couple of months ago, it's a safe bet we'll see it at some stage.
The last entry to be released in the Soul series was Soul Calibur V in early 2012. A high definition update of the third game in the franchise titled Soulcalibur II HD Online is expected to be released later this year.
Source : ign[dot]com