Best way for me to rationalize it is to look at a timeline where we have Fremantle lifetime (up to it's last updates), Harmattan alpha to final release, MeeGo releases, a future Nokia productized MeeGo (RPM!). These don't go on a straight line, more like parallel ones.

Harmattan is obviously closest and would be the first one feature complete. MeeGo develops alongside and pushes out versions which we have ('community'/MeeGo) project support for on N900. Nokia puts on their differentiation at some point but I have no idea how that'll look like (I can't tell the future).

This project would track Harmattan releases and end up in something similar to it's final release, but for N900. Logic dictates that a productized MeeGo will first come later.

This is to fill the gap between Fremantle lifetime being up and a quite usable MeeGo (RPM) on N900. Most people will be fine with Fremantle updates, some want the newest of the newest.

Also, what qgil said:

The first thing is to see if this initiative can deliver something technically usable and useful, with a real user demand beyind the usual tinkerers.