IDC’s latest research has found that IBM leads the global market for enterprise social software for the third consecutive year. IBM has more market share than any other vendor based on its 2011 revenue. The company grew almost two times faster than overall market, and has counts over 35 percent of the Fortune 100 as customers.

IBM’ s social software is now on its sixth release and earned $105.4 million in revenue, with a market share of 13.7 percent, almost doubling the performance of the closest competitor, Jive, which booked $65.3 million for an 8.5 percent market share. Communispace, Telligent and Socialtext rounded out the top five. IDC ranked Yammer, which is rumored to be an acquisition target for Microsoft, eighth.

Almost nobody thinks of IBM as a leader in social tool, but the company began making a big social push in 2010. For the last couple of years, IBM has been evangelizing social business, painting a picture where social is deeply integrated within users’ normal work streams. IBM is conducting road shows across the globe to spread its social business vision, which is based on four principles:

• Continuity –  existing applications and APIs continue to work in the new social business environment
• Convergence – alignment and consistency across product UIs
• Opportunity – IBM creates solutions using open standards and support for extensibility. This provides more opportunity for partners and developers to extend the platform
• Innovation – a focus on introducing new products and services to IBM social business portfolio

IBM has been tirelessly writing, and speaking about the importance social to business. It seems the company practices what it preaches. IBM has a massive internal social implementation that allows its employees to collaborate around the globe.

This may be the third time that IBM is at the top of the enterprise social stack, but it’s not a sign the company can take break. IBM must continue to innovate with new features and products because the market is filled with competitors ready to take the company’s place in the increasingly crowded market.