The Yammer team has been attentive to customers and quick to improve and extend its product, said Gautsch, e-learning director at Pepperdine University's Graziadio School of Business, which has been using the enterprise social networking tool since 2009.

"I've always appreciated their rapid [product] development and they've always been very responsive to their customer base," said Gautsch, who's a member of Yammer's customer advisory board.

Citing anonymous sources, Bloomberg Thursday that Microsoft is in advanced talks to acquire Yammer for about US$1 billion. Microsoft and Yammer declined to comment.

The news has generated reactions on social media channels from Yammer customers, industry observers, partners and competitors, with the debate focused on what the future would hold for Yammer's staff and product with Microsoft as parent company.

What's clear is that the acquisition would help Microsoft beef up the enterprise social features in collaboration products like SharePoint, Exchange, Lync and Office.