What are the Big Problems? I'm leaving this open-ended, there's no specific criteria for responses.
I'm interested in both your list and the reasons why. Submitting your list before reading others' contributions would be preferred.
Optionally: who is (or isn't) successfully addressing them. Individuals, organizations, companies, governments, other. How and/or why not?
I've asked this question periodically on several forums (G+, Reddit, HN) for seven years now.
I've written fairly extensively on my own views, reasonably findable if you wish, but my interest here is in gaining fresh input, resetting my own biases, and not colouring the discussion overly myself.