Google plans to announce in the coming month or so several customer  wins for Google Apps that exceed 100,000 users, according to Google  Enterprise Vice President Amit Singh. 
 
 The customer wins will include corporations, government agencies and  educational institutions, and are proof that cloud-hosted software is  starting to become mainstream among organizations, Singh said.
 
 "You'll see us announce in the next four to six weeks some very, very  large customers, with hundreds of thousands of users on at one time,  moving to Google Apps," he said in an interview.
 
 Google launched Apps, a cloud-hosted collaboration and communication  suite, in 2007 primarily for small businesses, but Google has been  adding enterprise IT features to it regularly to attract CIOs and IT  managers from large companies.
 
 Although most collaboration and communication software remains  on-premise, a market dominated by Microsoft and IBM, enterprises are  increasingly more comfortable switching this type of software to the  cloud.
 
 This way, vendors host and maintain the software on their data centers,  so customers don't have to buy hardware for it or spend time and effort  managing and tuning the applications.
 
 In addition, suites like Google Apps have been built from the ground for  users to collaborate on documents, doing joint editing on files that  are stored on a central server, instead of having to email files back  and forth among members of the workgroup.
 
 For Microsoft, the stakes are high in the coming year and beyond, as it  seeks to hold on to the large user base of its communication and  collaboration products like Exchange and SharePoint when they decide to  switch to the cloud model.
 
 Microsoft's cloud offering in communication and collaboration is Office  365, launched this summer as an answer to Google Apps and other similar  products, whose vendors hope to lure customers away from Microsoft's  on-premise products.
 
 Reiterating comments made recently by other Google officials, Singh said  that Google Apps customers can also expect to see a version of the  Google+ social network designed for workplaces.
 
 This enterprise version of Google+ is already in use internally at  Google, where it has been a hit, increasing productivity within teams  and improving the way people collaborate, Singh said.
 
 "Our next stage is to bring this [version of Google+] to the enterprise  so Google Apps customers can start to use the capabilities alongside  Google Apps to connect all the dots," he said.
 
 When the workplace version of Google+ becomes available, Google Apps  will gain an enterprise social-networking component at a time when  adoption of this software is expected to take off.
 
 The market for enterprise social collaboration software, which offers  Facebook and Twitter-like capabilities adapted for workplaces, will grow  at a compound annual growth rate of 61 percent through 2016, a year in  which the market for these products will reach US$6.4 billion, compared  with $600 million last year, according to Forrester Research.
 
 Companies like Jive Software, Socialtext, NewsGator, Yammer and  Telligent have been providing this type of software for several years,  while vendors like Microsoft, IBM, SAP and Salesforce.com have been  adding this functionality to their broader business software as well.
