There's absolutely no question that Android developers are doing great things, and Chris is also right that "building a community" always takes some time.
Yet, one wonders how much of this is a "I can't sharpen my axe, I'm too busy felling trees" argument. If no resources are spent on making Android more accessible and easier to accept contributions from the community (note: I am _not_ talking about upstreaming their own work!), the gulf widens all the time, and if the community would be able to contribute even only 5% of the work on bug fixes and features (a not very aggressive estimate), this is now work the Android core team has to do themselves or it doesn't get done. So, the platform loses out and the spiral works downwards.
This is Google. It's not as if they'd be hard pressed to put a team of 1-5 engineers on it to work on improving community interactions, accepting contributions (and perhaps help them get it right), and improving the bi-directional code flow.
And it might be a good way to identify and recruit new talent. This seems to be something Google is willing to invest quite a bit on, so maybe spin it like this? ;-)