Today, Zimbra announced that they have been acquired by Yahoo! This is a significant announcement both for Zimbra and for Software as a Service (SaaS).Zimbra is a full-features personal collaboration system (think a combination of Microsoft Outlook and Exchange) written as an open-source system with an AJAX (Asynchronous JavaScript and XML) client. I have been using Zimbra in a small-scale environment delivered as SaaS by OnDeckTech in Chicago. As a working environment, it is very effective, and its standards-based integration with everything (including my Mac and its Apple Mail, iCal, and Address Book) offers exceptional function.Where is this going? Good question. It’s clear that SaaS is gathering momentum and coming out of the the hype stage and into the productivity stage. Collaboration tools have led the way in this part of the marketplace, including e-mail, calendaring, and document sharing. There will continue to be evolution of applications in this marketplace.What are you using? Where do you see this going? Careers