W3C specifications only hit the final "TR" stage when there are at least two independent implementations. This does create a chicken/egg scenario for Microsoft as they won't implement specifications until they're finalised, which means it's up to the more
flexible and supple development groups at Mozilla, Apple, and Opera to implement them first, which means IE will always have to play catch-up.
Microsoft needs to change their policy so they'll at least implement the major things that are unlikely to change, like rounded corners and client-side databases,
I somewhat agree with your opinion that Microsoft needs to make a move and be more active. But implementing the standard partially is also not a good solution. IE had been non standard in the past and have bad reputations, even now after IE is fully standard.
You definitely do not want make those people to come back and start pointing fingers at IE anymore.
What I think Microsoft needs to do is to have some kind of a fork from ie for community review. Whatever they call this product, this will completely for review only and will never see an official release. The product may only consist of the trident engine
without any bells and whistles on it. That way Microsoft can get community reviews while contributing to the standardization process. Microsoft can even put a proof of concept on new suggestions there and noone will probably complains about it.