The lack of proper desktop on the two handset versions of meego is something a lot of TMO users have been complaining about (lack of widgets and easy access to some shortcuts and contacts, personalisation, etc..)

I believe it should be possible to implement the desktop concept at application level. It is not much more complicated to "go to app grid", "select desktop app" than "press home button", "select desktop".

The desktop app can be done in several steps: first just a grid where shortcuts/contacts can be placed at will, then addition of several desktop with swiping and hiding, then (more complicated) reimplementation of widget manager within the application.

Last step would be to ask Nokia to open the application launcher screen and have the opportunity to replace it (there was a thread on meego handset forum where we could ask some components to be opened). It would rock to have "event panel", "desktop panel" and "open applications panel".

I am ready to put some resources into such project as I can code, but be aware that even Nokia finishes more stuff than I do (ie if I try t do it, it will never happen).
I still believe that this could be very useful so I hope some of you are interested.

cordia? that ports the hildon desktop to meego. not sure about harmattan

Cordia is a much bigger project, it implements a whole UI on Meego core.
But it might be possible to get some inspiration there as they reimplement the desktop (in Qt?) among other things.

Isn't the GUI just a service? Can't we just create another GUI and make MeeGo fire it up instead of the proprietary one?

I understand that harmattan UI is closed, but can't it just not be used, or the loader/core/whatever is locked in some way to prevent it from starting any other GUI? It could even lead to an UI switcher, a la android, so user can change between default MeeGo, harmattan and Cordia/hildon at will.

having a custom UI would be cool, but you would likely lose the swipe functionality

Agreed. A GUI switcher would be nice, but neither meego stock UI nor cordia can currently compete with the Harmattan interface (which I could not try myself, but has pretty strong reviews). Improving on Harmattan UI is certainly more feasible right now.

just implemente a 4th desktop shouldn't be hard.

Except by the fact that it's closed? don't get me wrong, I would love a 4th area, specially witha iida like interface :
http://www.youtube.com/watch?v=0S6NMH4ry-4

A cool exercise would be making a switcher to change between the original open MeeGo UI and Harmattan UI. It would open doors to people create their custom UIs, like happens in Android right now - and we could use the MeeGo UI and add more stuff to it.

That's why I was thinking of a standalone application. In that case the "desktop" is UI and platform agnostic.

The home screen is open source. "Always" has been.

https://meego.gitorious.org/meegotouch/meegotouch-home