The social network, which provides extensive stat tracking, head maps and clan support for Modern Warfare 3, has received four million account registrations, of which one million have signed up for the premium package.
So far, more than 80,000 Elite clans have been created, while 100,000 user-generated videos have been uploaded since it launched earlier this month.
Despite the impressive figures, the service experienced a number of functionality issues when it first launched, prompting Activision to offer premium members an additional month on their annual subscription.
In response to Call of Duty: Elite's launch problems, Activision's Eric Hirshberg today apologised to fans.
"The demand for Call of Duty: Elite at launch was so overwhelming, that for the first several days, the service did not perform up to our or our fans' standards. I want to personally thank our fans for their patience.
"Our teams have been working around the clock to get the service scaled up to meet demand. I'm very pleased to announce today that the service is now performing stably and anyone who wants to try Call of Duty: Elite is now able to do so."
Call of Duty: Modern Warfare 3 was released for the Xbox 360, PS3 and PC on November 8.
> 'Call of Duty: Modern Warfare 3' review
> 'Modern Warfare 3' midnight launch in London - pictures
Watch the Modern Warfare 3 live-action trailer below: