The Debian team have confirmed that they'll be releasing Debian 4.0 later this year:

The Debian project confirms December 2006 as the date for the next release of its distribution which will be named Debian GNU/Linux 4.0 alias 'etch'. This will be the first official release to include the AMD64 architecture. The distribution will be released synchronously for 11 architectures in total.

The press release has more information.

I bet you're hanging to mirror all those files - you're probably also hoping that some of them share the same filename