First, there was Microsoft Deputy General Counsel Horacio Gutiérrez, who heads up the company's intellectual property group. He declared in an that Google, with its Android operating system, "stood on the shoulder of companies like Microsoft" that have invested billions in making operating systems more efficient.

Then there was Tom Rizzo, director of Microsoft Office 365, who came out with guns blazing in a company blog. He accused Google of a "spaghetti" approach to application development. "Its products are like spaghetti," he wrote. "Google throws them up against the wall to see if they stick."

seemed to be targeted at Google's policy of dropping support for older versions of browsers once a new version comes out. Here's what says: "We support the current and previous major releases of Chrome, Firefox, Internet Explorer, and Safari on a rolling basis. Each time a new version is released, we begin supporting that version and stop supporting the third-oldest version."

Rizzo argued that the policy hurt business users who don't have the same flexibility that consumers do to switch to a new version of a browser. "If I were running a business using web-based productivity tools from Google, learning about their discontinuation of support for older browsers would make my hair stand on end," Rizzo wrote.

"I'm sure it is a lot easier for Google to limit the number of browsers it supports than to address differences in the browsers," he continued, "but if I were an institution or business relying on Google Apps, it would be completely unreasonable to force version upgrades, and unacceptable to expect that users will always have the latest browser versions."