It has been known for quite some time that Yahoo are trying to make bold changes internally. Products have been shut down (eg. Yahoo Live and Geocities) and it has been rumored that Zimbra has been up for sale for quite a few months by now.
If VMware ends up acquiring Zimbra it’s a very strange deal, but it might make sense. With VMware’s virtualization expertise, they might very well be able turn Zimbra into a powerful virtual appliance. That could work both sell it as a software appliance (just the virtual machine) as well as a hardware appliance (hardware). Combined with VMware’s virtualization product line, they can target everything from small business (VMware Server) to large enterprises (ESX). This could be a very serious threat to Microsoft Exchange.
However, the real question is why did Yahoo buy Zimbra in the first place? I mean, Zimbra is a solid product and all, but Yahoo never really took the advantage of it. Yahoo never even really integrated Zimbra into their product line. It could very well have the missing piece to bring Yahoo Small Business to a competitive product instead of just a big outdated joke.
Looking back at what happened to Zimbra after Yahoo bought it in 2007, not a whole lot of things have happened. Yes, the number of users have grown to more than 40 million, but that was mostly due to the deal they locked down with Comcast.