I don't agree.

I think Google is providing a "least common denominator"/"reference platform" for Android, and then leaving the bells and whistles to the specific vendors. That's what's going on with both the Samsung and HTC Hero, it seems like.

And, that Google "vanilla Andriod" doesn't seem immature to me. It doesn't have a lot of frills, but it has what it needs. And it does expand over time. The immature phase were those first 3 months when we found out every key stroke was being sent to a root shell, under the hood... and things like that.

What seems immature in the Android arena is: the app ecosystem is still growing from its initial offerings into a more rich environment, and the add-on vendors (HTC, Samsung, Motorola) are still emerging. But neither of those is Android itself. I could, frankly, be quite happy with my G1, running Vanilla Android, for quite some time. Its limitations aren't due to lack of maturity, but lack of common goals (I want tethering, T-Mobile doesn't want me to have tethering; that kind of thing).