Earlier today, Nameco Bandai Europe announced Soulcalibur: Lost Swords will be a free-to-play title for Sony's PlayStation 3. The game will be released exclusively on the PlayStation Network. The game is reported as single-player only. Nothing on other regions yet.
In an announcement that Joystiq got their hands on, the game is described, "Lost Swords is a "free-to-play single-player experience and will feature numerous famous fighters including Siegfried and Mitsurugi."
The tweet on this game only states Europe, and there is no specific information on a release in North America. Given, however, that they have filed for a USPTO Trademark back in July of this year, it's likely they will be adding additional regions as things move along.
We should hear more about this coming from next week's Tokyo Game Show.