Sorry, I didn't mean to come across as a dick. I'm glad that you've taken the feedback of your readers into consideration.

I'm a big fan of Redis, and it's a key component of our stack. Sorted sets are useful for a lot more than just leader boards, though that is a good use case for them. It's a bit late here, so I'm not feeling up to writing a big post, but I'm considering writing my own blog post on my experiences with Redis.