Thinking different - Schema Design for Users, Items, Tags

Hi

one of the most challenging parts of switching from MySQL to Mongo is 
giving up thinking in relational design pattern the way I have done it 
the last 25 yrs or so...maybe someone can tell me if I am on the right 
track here:

Let's say we have a very common application with Users / Items and Tags. 
User should be able to add items and tag them.

I am sort of referring to this article here: 
http://tagschema.com/blogs/tagschema/...latedness-in.html



When I think about this I tend to design it with 3 collections (user, 
items, tags) and having in each of them sub-arrays with object-ids. 
would this "normalized" approach be the correct one? Or am I just 
thinking in old patterns?

Thanks

Sven