Servicing betas

Background: yesterday, Security Bulletin MS05-038 was released, a cumulative update for Internet Explorer, fixing two critical vulnerabilities, and one moderate. The IEBlog posting clarifies that these fixes were included in IE 7 beta 1 and Windows Vista beta 1.

What's Microsoft's policy on security patches for Beta software, specifically IE7? I realise that the recommendation is only to run beta software on non-production systems; however, many beta testers and some MSDN subscribers are using it as their main browser (conjecture from posts here and other forums), and the software has been made available on file-sharing networks - some 'bleeding edge' ordinary users are also using it. Back when IE betas were a more common occurrence, there was a site dedicated to them. The site still exists but has branched out more into a more general NeoWin/ActiveWin style of reporting.

As a developer, it definitely feels weird to talk about servicing unreleased software. But with the widespread use of such beta software - even if illegitimately distributed and used inappropriately - I feel that Microsoft has a responsibility to ensure that such beta software remains free of vulnerabilities.