It depends on who creates the Beta applications. Generally, Google's "Beta" releases are bug-free, but sometimes with very basic functinality in the initial phases; they will keep adding features to the basic design, and many applications remain in Beta for quite some time.
For more than you really want to know about Beta's you might want to read my blog here about Beta Releases and Project Management:http://www.bleepingcomputer.com/blogs/jgwe...p?showentry=449
I think you should always keep in mind two important things about Beta applications:
1. These are generally published so that many people can test them. The more fingers using it, the greater the chances that problems (minor or major) will be found. Some of these Betas work quite well, but on the other hand, some still have poor interfaces, incomplete parts, and downright bugs. Unless you are prepared for spending some time troubleshooting problems, and are somewhat knowledgeable about computers and software, you are safest to wait until the application is released in a stable version.
To get an idea about the status of each staged Beta Release, always carefully read the "release notes." Most of the time, you can also find tester's (or public) discussions of the beta release; these can quickly tell you if the application is useable and somewhat reliable, or still needs a lot of work.
2. UNDER NO CIRCUMSTANCES should you use ANY Beta Release (even if Beta 75) for any "mission critical" uses. Betas are simply no substitute for applications that you can absolutely (well 99.9 percent absolutely) rely upon. Don't, for example, do your income tax on a Beta spreadsheet!
I hope this helps you to understand Beta releases.