Showing the problems without requiring login would really help conversion. Let people invest time and effort on their solution, then make them log in to share.
I totally agree. Having glanced over the page while browsing mindlessly, I closed the tab immediately after the 'Login with GitHub' popped up.
I am simply unwilling to provide my authentication details to a page without being presented with at least the basic functionality.
I'm a huge fan of doing a little code kata in the morning to keep things fresh. I just use a little library of problems and often revisit old problems and find new ways to express a solution. Will you be able to revisit old problems and submit new solutions to them?
I really like the idea and will try it out once the range of languages increases. I'd be interested once C, C++, Python, or Common Lisp are supported.
Exorcism is being made by one of my co-workers, Katrina Owen, and eventually will probably be open-sourced. I'll make sure to pass along everyone's suggestions to her!