My brother saw it on On Demand and found it reasonably entertaining. I'm not really sure where a sequel would go -- maybe flip the concept over so the world's in anarchic chaos 364 days a year and one day a year everyone abides by the laws
-- though that's not something that ever stopped Hollywood before.
Basically, if anything cheap does well at the box office (re Blair Witch Project, Paranormal Activity, Insidious, Saw etc. etc.)
then expect it to be sequelized to death until any freshness in the original film is ground into sawdust and until moviegoers decide they've had enough.