So what is a Perpetual Beta? Lets look at some dictionary meetings before going further:

Perpetual – perpetually – In a perpetual manner; Seeming to never end; endlessly; constantly
en.wiktionary.org/wiki/perpetually

Beta – A software release is the distribution (whether public or private) of an initial or upgraded version of a computer software product. The software engineers and company doing the work decide on how to distribute the program or system, or changes to that pre downloads and compact discs.
en.wikipedia.org/wiki/Beta_(software_development)

Perpetual Beta – Perpetual beta is a term used to describe software or a system which remains at the beta development stage for an extended or even indefinite period of time. It is often used by developers in order to allow them to constantly release new features that might not be fully tested.
en.wikipedia.org/wiki/Perpetual_beta

Perpetual Beta in Web 2.0 is used to describe an online service which remains under constant development. At great example of this was Gmail.

Google’s Gmail service launched on the 1st of April, 2004 as an invite only service. I remained as an invite only service for nearly 3 years before becoming open to the public (7th of February, 2007). It was still labeled a Beta for another 2 years until the lifted the Beta labelled along with the rest of the Google Apps Suite on the 7th of July, 2009.

During its time in Beta Google constantly introduced new features and changed its services. Introducing new languages, enabled IMAP support, increasing the mailbox size, integration with Google Docs, custom themes, Google labs and many more. Click here for a history of Gmail.

So why label something a Beta? Generally if something is in Beta you can expect some things not to work, and problems arise. This is all part of harnessing the collective intelligence to develop the product, find bugs and provided feedback to make a better product. Without having a web 2.0 application or service you will be stuck in the traditional software life cycle which can cost more, take longer and not be as effective.

So why take the Beta label off after so many years? From an Infrastructure perspective you don’t deploy products that are in Beta. You deploy products that a ready that have no expected bugs or problems. Google understood this concept so after around 5 years the finally took the Beta label of. This changes how a business can look at a product and it will allow business to evaluate Gmail and related apps as a potential solution. Previously this would have been ruled out straight away because it wasn’t ready, it was in ‘beta’ and a business can’t afford to have systems that are un-reliable.

So while the main service of Gmail isn’t in Beta anymore there are still more features on going. Google introduced Google Labs which is an opt-in only service that lest to add features and functionality that are in a ‘Beta’ phase. I actually use some of these myself such as multiple inboxes, offline synchronisation, youtube preview in e-mails just to name a few. Once these have been tested enough they might make it to the core functionality of Gmail. So this is an example of a Web 2.0 service that is on a constant Perpetual Beta.