Competition between Microsoft & Google intensifies with the release of cloud-based Office 365.

At an event yesterday in New York city, Steve Balmer of Microsoft hosted the global launch of Office 365.

Analysts have noted that in recent years Microsoft has been making big bets on the cloud with products like Azure, but Office 365 is by far the company’s biggest push into cloud software.

With this bundling of its Office, SharePoint Online, Exchange Online and Lync Online onto a cloud platform, which some observers are viewing as a rebranding of its BPOS (Business Productivity Online Suite), Microsoft has fired a shot across the bow of Google Apps.

Tom Rizzo, a senior director at Microsoft, asserted in an interview with eWEEK that businesses were trying Google’s business-cloud offerings before shifting back into Microsoft’s camp. Google executives took strident exception to this, arguing that Google remains the leading choice for businesses interested in cloud-based email and collaboration.