Why not just use OpenSolaris?
OpenSolaris is not quite as rich in packages as Ubuntu, nor is the community as active, so there are benefits over using Nexenta compared to OpenSolaris. The latest stable release, NexentaCore Platform v2.0, is based on Ubuntu 8.04 LTS (long-term support), which is better known as Hardy Heron. It uses the 104+ build of OpenSolaris with critical patches and includes a load of popular packages, including dpkg, apt, gcc, binutils, Perl, Python, GTK, QT, Apache, MySQL and Exim4.