Free multiplayer access begins Friday, December 11th at 12:01 AM Pacific through Sunday, December 13, at 11:59 PM Pacific.
Check the PST here http://www.timeanddate.com/time/zones/pst
To get started, log on to PlayStation Network during the free weekend period, launch your favorite multiplayer game, and you’ll instantly have access to multiplayer with your friends. There’s no membership commitment required to try out online multiplayer during this period.
Playing online usually requires a PlayStation Plus subscription, which costs US$10 monthly, US$18 for a three-month bundle or US$50 for an entire year. A Plus membership also guarantees at least two free games and a lineup of discounts every month.
Are there any games that don't require a subscription to play online? (not including this weekend, obviously :))