Like you said this might end up in a religious war to some however I feel that if you plan on doing a serious project you should look into your requirements and see what you actually need and possibly think about scalability as well and then pick your framework from there. All frameworks have overhead of some kind and the best and probably also the slowest would be to write it your self, that's my view any ways and I've written a couple but they are very small with limited functionality as that was all I needed at the time.
Its interesting to hear other peoples views though. Lately I've been looking into Google Guice and Sitebricks which is a pretty interesting framework but nowhere near any of the other ones out there as it is lacking in functionality.
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