I absolutely love the thought of this. I think getting a pre-screened idea every day will be a great way to practice validating ideas, contemplating customer dev tasks, thinking through potential MVPs and determining what "the next right step" should be. If nothing else it will expose people to niches/businesses/processes they would otherwise never know about or consider, which could lead to even more/better/different ideas.

The community aspect sounds interesting too because if you've had a handful of stinkers in your portfolio (and who hasn't?) then you might not trust your own judgment much anymore. Assuming the community is well-moderated and "judgement/asshole free" there could be some MASSIVE strides made by devs who need help in this department.