What are some alternatives?
Meetup - Helps groups of people with shared interests plan events and facilitates off line group meetings in various localities around the world.
LynQ - The People Compass - Real time location tracking even when phones fail
Collaborizm - Meet New People. Build Amazing Things. A workspace for aspiring Entrepreneurs, Engineers, and Creatives.
Plane - The social icebreaker. Connect with new people in new places
Emamo - Simple event tools for organizations. One central hub to manage your events and members — all year long.
FriendsTonight - Meet new friends to join your friends, tonight