Helium, the branch that will become the next major release, is now buildable for both i386 and amd64. Nightly builds are operational too, you can get latest images from http://builds.vyos.net/iso/development/helium/.
Release is planned for May or June. The roadmap is not yet set in stone, so it’s open for your suggestions and patches.
Helium will be based on squeeze. To avoid unexpected release delays due to fragile code incompatibilities with new userland, we will squeeze the last bit out of squeeze while it’s still supported and refactor the fragile parts.