Planio was started for and within Bolidea, a startup accelarator that runs multiple products and projects at once. Bolidea could not find an agile project management tool that was:

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  Simple yet complete - not overflowing with sections and features
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  Made for the whole team; able to handle projects outside of software development
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  Effective for shared resources and distributed teams
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  Fully collaborative and in real time

Planio is still quite young (we started late 2009) so we know there's still lots to do. We use it daily to develop Planio, wo we also feel your pain where features are pending! So far, for us and many others, it's proven quite effective. It will only grow better.