The hard part here is building a community of people who will contribute problems and content around problems. This might be bootstrapped at the beginning either by putting effort in searching the web for such problems, and asking experts around the web about problems, and slowly building a database.

Such content could be a pull for some groups of people, many of them will be more interested in solutions ,but some will be a source of more problems.

And there's also the question of exposing the information in such a way to encourage innovation and not just reading.Not sure what the right way to do this, but it's interesting.

It's not easy to create a high quality content/community site around this , but when solved well this could be a really valuable site.

[1]http://www.reddit.com/r/realproblemsolvers

The key to making this work would be an adequate capture of the context as well as a description of the problem. In the product design world we use "Personas" as a vehicle for packaging problems into descriptions of user needs. They give the user a demographic and allow the designer to imagine that person and how they might use a potential solution. This allows to designer to avoid imposing their own preconceptions or doubts onto the context or idea before it is even a mere wisp of a concept.

If you can capture this in a spam free, usable and elegant website I reckon you'll be on to something. Not sure how you'd monetise the output, but then that's why I've never finished the 50 or so website projects I started.

I'll look these comments & site over and discuss with friends a bit; obviously, creating a site is the easy part