Nope, this is an awesome idea, I've had it myself several years ago.

My immediate reaction to your implementation:

- C# is icky.

- Would be cool to automatically compare performance of solutions, e.g. timing, memory footprint, etc.

- "Run" button doesn't appear to provide any output?

When I had this idea, I also wanted to be able to provide sample inputs and outputs, and have all potentially matching functions run, to see if any match.

In general, you've hit the problem of building a community without an actual community magically appearing. Keep at it.