It's vanilla Meego that's stripped down (IE no proprietery software but it already has working phone support). Not Harmattan-Meego (which the N900 isn't getting anyway). What will happen is the community will be responsible for any backporting of parts in Harmattan-Meego to Vanilla Meego. Like Flash, Skype, etc..
I wouldn't make that a statement of fact. It's dependent on the community to backport the closed bits. So it's up to whatever's left of the developmental community, and from what I've seen we've already lost a few good ones.