Samples of the upcoming 2.0 Release are starting to filter their way out to FTP servers. You can find these files in pub/OpenBSD/2.0 on each listed FTP server.
NOTE: please do not fetch binaries directly from cvs.openbsd.org but instead use one of the mirror sites.
The file structure of each FTP server is roughly:
.../OpenBSD/2.0/
.../OpenBSD/snapshots/
.../OpenBSD/X11/
.../OpenBSD/src/
.../OpenBSD/tools/
If you add a new FTP mirror site, please contact the FTP maintainer.