The milestone comes just five months after SCVNGR released its consumer-facing iPhone and Android apps in the U.S. By comparison, Gowalla reported 450,000 members in early September, and Foursquare will hit 4 million members this week.
In celebration of the milestone, the Google-backed SCVNGR will reward user number 500,000 with an Apple iPad.
Priebatsch also shares that SCVNGR should hit 1 million users by the end of the year, which would mean that the company is now signing on upward of 150,000 new users per month -- or 5,000 per day. That's still significantly less than Foursquare's estimated daily rate of 20,000 new users, but impressive considering the former startup's youth.
On the enterprise side of things, Priebatsch says that SCVNGR's enterprise clientele now includes 1,000 different businesses, ranging from the likes of Sony and Warner Bros. to Harvard, Zip Car and the U.S. Navy, using the service to encourage checkins and challenges. There's also reportedly 10,000 plus locations offering rewards via SCVNGR.