Today, we release version 2.1.0, which mainly is a bugfix and stability release:
http://www.instantreality.org/downloads/
Notes for Linux users:
Currently the only officially supported distribution is Ubuntu 10.04 (old Ubuntu 9.10 is no longer supported). Debian is updated to version 6.0.
Furthermore, for distributions like RedHat / CentOS please refer to the daily builds section.