Eli ...
*store your work on launchpad! *use the native client feature of chrome to have a webclient without needed of programming a plugin (it is easy and will run even on android phones) *authenticate user with web2.0 sites like passport, openID or fbook *stop talking to the old dev team - look forward and try to become compatible to nx(4?) again - their server is much better.
You mean the "Get Ready for NX 4.0" that's been "almost released" since Jan 2010? (also remember we're talking open source here so for the price difference of x2go ($0) vs v3.4 Enterprise NX server @ $1500 per 2 cpu server... there is some advantage to x2go for many people.
I think there is also a lot of great work being done in SPICE which may be into upstream sometime next year. Its architecture is very good but its still "new" and I have more than a few crashes all the time. But it is open-source and the development groups are *very* active. One drawback to me with it though is that SPICE does rely on either xen or kvm on the server side.
However, even the current x2go provided capabilities others mentioned offered and in some cases x2go's actually worked better (audio ?). nx4.x its still under development and not released as is the next version of x2go. It will be interested to see both when they are both available.
I agree that the x2go work should get put on launchpad. If they want to get into the official repositories for Ubuntu that is a criteria and I'm assuming that would be good goal for any remote desktop project.
Authentication via oauth, openID etc as you say is also a great capability that you see being used more and more by lots of applications.