We'll now that I've been asked for my opinion (That's a dangerous thing!)
Badges are awesomesauce and should be for things like number of likes, number of posts, number of helpful replies, etc. but they could also be for things like 'first linked post' or 'first share on LinkedIn/Twitter/etc'
The challenge is rewarding real content and not just random posts. I like the idea of task based badges especially since there are so many different products. Maybe a 'level' system for each of the products -- APM, Infrastructure, Synthetics, etc. where you progress from basic ('padawan' - can you do the Star Wars thing??) to Jedi Master (let's keep the theme going).
I know some other communities reward participation in marketing driven events with points. I feel like those should be kept different from the rankings for knowledge and contributing to the CoP of New Relic.
Maybe you can just steal the Stack Overflow model?