Last week, Mozilla programmers and executives were jubilant when the release of Firefox 5 marked the successful transition to a more competitive rapid-release development cycle.

Now, with a backlash from corporations and others who aren’t equipped to handle that pace of change, things aren’t quite so sunny. The organization and its community of supporters have begun some soul-searching about how to reconcile the conflicting priorities–developing software quickly but not leaving users behind.

Mozilla has concluded that Firefox isn’t for corporations whose Web use doesn’t move at the speed of today’s Web, though. That decision frees Mozilla from catering to that audience, but it also means that audience is more likely to choose a rival browser–Microsoft’s Internet Explorer being the most obvious candidate.

The tension mirrors one in standardization circles between two groups overseeing Hypertext Markup Language, the programming language better known as HTML that’s used to describe Web pages. One group, the Web Hypertext Applications Technology Working Group (WHATWG), has moved to a “living” document whose HTML specification continually evolves. The other, the World Wide Web Consortium (W3C), standardizes a snapshot of this specification through a process that moves at a much more stately pace for those whose products and certifications also do: its HTML5 standard isn’t due to be officially complete until 2014.

Deliberations about the Firefox support issue have surged on a 220-plus message discussion on a Mozilla mailing list.