SketchFactor writes on Bungie.net that the .NET conversion has been delayed at least until Monday. You can amuse yourself in the interim by reading the Bungie.NET FAQ.

Of course, when Microsoft bought Bungie, there were plenty of accusations flying around that MS wanted the Mac port killed, or the PC port delayed to avoid cutting into Xbox sales, and various other things, most of which made no sense. However, despite the usual sense of humor that permeates Bungie's communications with its fans, this remark strikes me as unintentionally funny, in answer to the question "I heard that there were lots of security holes and problems with .NET Passport...":

The .NET Passport is used by some of the top businesses and websites all across the world. The technology is proven and security is foremost in the mind of Microsoft and its engineers. For more info, please visit the .NET Passport Q&A mentioned at the top of this page.

The more conspiracy-minded among Bungie's fans will surely believe that .NET was not necessarily chosen solely for its technical merits, but because it's a Microsoft technology. After all, previous iterations of Bungie's community presences-- all very impressive-- got along quite nicely without .NET; the free software conspiracists will no doubt view this as an opportunity to replace internal use of Open Source Software, in this case the programming language Perl, widely used on Linux, BSD and Unix platforms, with a proprietary Microsoft framework.

Of course, if the system works, and works well, it's likely no one will mind such a transition-- after all, it's all about the games, not the websites.