[EricE]

>Is there an open source solution for processing streams of structured and unstructured logs and routing then onward?

https://securityonion.net

It doesn't route them onward - it will collect, aggregate and provide you the tools to correlate/analyze logs across your environment. Enable the built in network monitoring tools too and you have not only a powerful tool to help you with application management, but security as well (hence its namesake).

Beware - in pealing back the layers of your environment you can really get sucked in. I never seem to have enough hardware to do what I want with SO but it's pretty amazing what you can do with it.

EDIT - wow, I'm a little shocked that no one else has brought Security Onion up. I guess they need to up their advertising game!