Google's efforts to allow developers to create social-networking applications that will run on multiple websites are already paying dividends for one company. Plaxo, the first company to launch applications built using Google's Google's OpenSocial APIs, has seen a huge surge in traffic in the three weeks since the APIs were released.

John McCrea, Plaxo's vice president of marketing, said the company's Pulse social network has seen its traffic jump from about 200,000 around the OpenSocial launch date on November 1 to more than 1 million on November 14. From the moment OpenSocial was announced publicly, Plaxo Pulse "has experienced a surge so strong that we had to expedite a hardware order, and shift focus temporarily from the new features to scalability", McCrea said. "In a single day, the rate of wiring up the Pulse social graph jumped by an order-of-magnitude," he continued.

The Pulse offering allows users to build social networks based on the content that has been produced by the contacts in their electronic address books. Using OpenSocial, Plaxo allows Pulse users to create distinct professional and personal profiles that include photos, contact information and settings. Any application written in Google's OpenSocial can be embedded in the profiles.

The traffic gains show that Plaxo's statement when it launched Pulse in August that the market was ready for an "open social network" was correct, McCrea added.

"The idea was that we could play a role in the emergence of a social web that was as open as the web itself," according to McCrea. "We let users bring in content from the sites they were already using, and we let them take their data out through a variety of mechanisms, including RSS and a lifestreaming widget."

Kristen Nicole, a blogger on social-networking site Mashable, noted in a blog post that Plaxo's success says a lot about the potential for OpenSocial.

"But this seems to be a particularly unique situation for Plaxo Pulse, as it operates from the standpoint of highlighting your existing relationships," she noted. "Wrap that up in an application that further works from these relationships, and you have a convenient manner in which users can extensively expand activity going on within their Pulse accounts."