The Zimbra Web Client is a fully integrated AJAX application with capabilities extending beyond what is possible in traditional desktop clients. Key advantages of Zimbra web email and collaboration:
Zimbra is partnering with some of the largest VoIP providers to provide a joint Unified Messaging offering for their customers. Zimbra has developed a Unified Messaging Zimlet that allows users to quickly launch calls, conference calls and to access voice mail from within the Zimbra Collaboration Server. Zimbra's Unified Messaging Zimlet leverages the SIP protocol, an open standards based protocol, thereby providing Zimbra's customers will have the maximum choice of VoIP providers.
The initial offering of Zimbra Unified Messaging is based on a partnership with Asterisk, the leading open source VoIP provider. More information is available in the announcement.
Zimbra and Digium plan to release a Beta of Zimbra Unified Messaging as part of the 3.2 release.