Seriosly, though, please don’t. I hate it when packages clutter my browser console or the server logs.
If the log item is a serious piece of information that needs to get recorded, perhaps for identifying problems later, and that it happens only once in a while, maybe it can be acceptable. Otherwise it is just noise. Especially in the browser. In fact I kind of consider a security threat due to its revealing nature.
You can perhaps make it opt-in. Allow your package to accept a configuration paramater that turns logging on/of, better yet separately for the server and the client.
I wish meteor had a defacto logging framework into which packages could individually register their namespaces with and the app developer themselves could configure what gets to be displayed, what gets to be diverted elsewhere etc.