I received my Windows 7 Ultimate Commemorative Edition today from Microsoft for being part of the beta program. As it happens, I tend to find myself running a lot of beta software.
Beta software is software generally regarded by its author as not well tested or not reliable. Sometimes beta can also be used as a marketing gimmick. Companies like Google have done this with Gmail and Google Wave where only a small amount of people were initially using those products and others could only be invited through invitations. This brings an exclusiveness to those products just like a club that only allows entry to those with invitations.
Anyhow, I run beta software mostly. The main reason is that the occasional problem I encounter with the software is educational to solve as well as fun. That doesn’t mean things always go well though. When the Office System 2007 was still beta, I used it for homework. There was a case where Word corrupted my document so that the file I sent to the professor could not be openned, and the version saved could not be openned. The professor was understanding though, and Microsoft was able to give me a way to recover the document, which was surprising. That is probably the most data loss I have had in using beta software.
Back when I was more involved with Mozilla Firefox, I would run the nightly builds. They were generally pretty stable for me. Mozilla inherited one of the best software engineering infrastructures I’ve seen from Netscape. They have a system integrating source control, issue tracking, and continuous integration. They have systems set up for each of their target platforms constantly building Firefox with the latest changes. If it does not build or the basic tests fail, the build is broken, and the build sherrif is notified. The build sherrif either gets the pertinent person to correct the problem or reverses the change to quickly get the system back into a relatively stable state. I’ve held an admiration for this setup.