It sounds like they tried to stuff too many "improvements" in to a single release. Roll back to 2.2, start cautiously adding the most desired new features, and release something much more modest than 2.4.

Maybe there should only be one major new feature added per release. And more frequent releases. A full blown SMP OS kernel is tricky stuff. It should be taken slow and steady, with a high frequency feedback loop from users.

Greed takes many forms. Trying to do too much too fast is a form of greed.