Is there any new functionality here?

No - you can achieve the same results by passing in weird strings in the Github search bar. I created this because I was frustrated I couldn't do a search for repos by popularity and date together.

Can I search for anything besides repos?

For now I have just done this for repos as that is the most common use case.

I don't see any results! WTF?!?

Your overzealous searching hit my poor API limit (its per minute). Take a few breaths and try again in a minute. Thanks!