Seems pretty interesting. And official MS support for running the whole thing on Mono, right now, isn't that pretty big?
But capability is half of the story. Tooling/ecosystems is the other half (re: MonoDevelop is still not up to the snuff).
This is starting to look like a pretty decent environment to work in.
While Windows ecosystems are gaining momentum, it's just not there yet.
Like you said it's just "decent environment", not better than what I use today.