Yes, I think we mostly agree on the problematics of this issue.

I think the problem with API's etc. is real, but then again, in the long run this will be an iterative process. If something isn't in the first release, we can add it to the next release

It's just hard to me to think of good ways to get community input for the specific issue of UI.

Generally companies... Ok, let's focus even more: generally UI's are not revealed in advance because of competitive reasons. If we would have shown the Maemo 5 UI plans at the time they were ready for the first time, any smart competitor would have not commented anything on them, picked up on the good ideas, disregarded others and probably even come out with their own device before Nokia. Then end consumers - who don't know and care about the process of how things get done - would be just left confused. Showing our own cards is a very basic problem, and I hope everybody realizes that. We will be the first company out with the device with the Maemo 5 UI. If you wouldn't believe your UI is an competitive advantage and therefore don't care about that fact, then we can all go home already.

So, either you hold your cards really close to your chest, or you then do the complete opposite, and do like Mozilla, and open up everything all the time, right from the start. If Nokia = Maemo and nothing more, and if Nokia could crank devices out faster than any competitor, then perhaps there would be more options. But since Nokia > just Maemo, even Maemo does not work in a bubble. Revealing some parts of Maemo UI would reveal ... elements of "Nokia UI" - see that however you want.

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Yes, members of the community could then give "free input", probably, but "free" here isn't truly free - it is with a rather large cost.