At my company we started with Graylog2 and recently installed Kibana3.
My personal opinion is that Kibana3 is more suited towards non-dev, while Graylog isn’t.
Kibana:
- Pretty dashboards
- Graphs, charts and images
- “panel” customization, adding parallel coordinate graphs for example
- Easy/flexible management of dashboards (they save directly into their own ES index)
- Easy deployment (just clone the Kibana3 repo and serve it with your fav. web server)
Graylog2
- Much simpler interface
- Plain log “analysis” and good search capabilities
- Built in authentication and user permissions
- Built in alert mechanisms for your chosen streams
We still have Graylog2 running in parallel to Kibana3, but I don’t think it will last for much longer. Kibana3 provides most, if not all, of the capabilities (that we needed), and on top of that it allows management friendly interfaces.