Plenty of large companies are getting behind MeeGo:

http://forum.meego.com/showthread.php?t=46

It's been said many times by qgil and others that with Qt 4.6 compatibility for Maemo 5 coming in the 1.2 update, developers can go ahead and write now (for Maemo 5) and run later (on Maemo and/or MeeGo).

I don't see a significant problem technically. If developers aren't releasing more software for Maemo, it's very likely because there simply isn't enough raw numbers of Maemo devices in user's hands yet to support the cost of releasing more commecial software. The N900 by itself hasn't sold millions and millions of units like the numerous Android phones or the iPhone - not yet. They had a long head start and it will take a while for the number of Maemo/MeeGo units to reach critical mass for software companies. But remember, things change very quickly in the mobile device world.

The N900 has sold really well, better than Nokia expected for sure. The success of the N900 and strong support it demonstrated for an open mobile linux OS may well be what convinced Nokia and Intel to finalize the MeeGo project.