Unix Review just posted a great review of Wildfire and Wildfire Enterprise. From the article:
"Wildfire really impressed me and I find it really hard to come up with a negative when it comes to this great IM server -- perhaps a Debian package would be nice for non-RPM distributions. Installation was a breeze as was setup. Working with the browser-based administrative interface is a joy. In fact, Wildfire is a beautiful, easy to use, configurable, customizable, extensible, and powerful instant messaging server."
The author also does a good job summarizing why companies should adopt XMPP (Jabber) as their IM protocol of choice:
"From a business standpoint, Jabber should be your clear IM choice. Because Jabber is an open protocol, it doesn't belong to anyone in particular, so there is no single company driving its destiny. Your business won't get locked down by proprietary formats. Jabber also uses a decentralized approach so the system is more robust. Best of all, any company can run its own private, secure, standards compliant, Jabber instant messaging server for little or no cost for the software."