The enigmatic, invite-only social search service Aardvark is opening up - the invites that have thus far been limited to one or so per month for a single user, will soon be extended to infinite invitations.

The company, which recently changed its name to Aardvark from Mechanical Zoo, provides a means for getting speedy, quality answers to questions from the comprehensive social network of the users.

The social search engine allows users to ask questions through an instant message buddy or email; and then branches out the asked questions to the users' list of contacts - and their further contacts - based on the information they can provide about the topic in question.

The San Francisco, California-based Aardvark is largely focused on user invitations, instead of being merely open for the general public, particularly because the outcomes from the use of its service are the best results when users already have friends using it.

The service allows users to practically grab quick friends by signing in using Facebook Connect - a platform which displays all of one's Facebook friends who are already using the service, with the provision of inviting those friends who are not.

The 2007-founded Aardvark - Mechanical Zoo - which launched into private beta in 2008 - is also testing an extremely promising sub-product under which people with similar interests will be grouped together.