Microsoft is launching Office 365 today (June 28), but the cloud computing celebration started yesterday at Zimbra — an open source email platform owned by VMware. In a somewhat surprising editorial spin, The Wall Street Journal yesterday positioned Zimbra as a major rival to Office 365 even before the Microsoft cloud suite arrived. Here’s why.

Sure, Microsoft competes head-on against Google and VMware in the cloud and virtualization markets, respectively. But The Journal in a June 27 news story gave surprisingly strong credence to Zimbra, which has been lining up SaaS channel partners over the past year.

According to The Journal:

The VAR Guy certainly agrees with that last line. But the Zimbra mention by The Wall Street Journal continues to catch The VAR Guy’s attention. Remember: Yahoo essentially quit on Zimbra and sold the business to VMware in January 2010. By February 2011, VMware was funding new initiatives at Zimbra, including an SMB partner and customer push.

What gave The Wall Street Journal the idea that Zimbra is a major force that Microsoft Office 365 must overcome?

Either way, Zimbra scored a major victory with the mention in The Wall Street Journal. Before the article, The VAR Guy suspects, most WSJ readers had never heard of Zimbra.

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