Nexenta is a complete GNU-based operating system built on top of the OpenSolaris kernel and runtime. The Debian system is used for software distribution and packaging to glue the numerous pieces together. However, Nexenta is not currently part of the Debian Project, nor are its packages present in the Debian database. It includes Apache, MySQL, Perl, Python, PHP, Firefox, Evolution, a software update manager, Synaptic package manager, Gaim, Abiword, administration and development utilities, editors, graphics, GNOME, interpreters, libraries, and much more.
OpenVPS is a set of software built on top of the Linux VServer aimed specifically at Web Hosting. It is not another set of kernel patches, but a set of scripts to create virtual servers, collect resource utilization information, and provide an interface to the customer as well as the administrator.