The .system.* collection namespace is reserved, but should not be. It's counter-intuitive and pollutes the namespace.

I suggest that all such system stuff should be moved to a separate table named 'system' or 'mongodb' (like in MySQL).

+ Safer
+ Less clutter
+ Users will see their own stuff, not the system stuff
(which they will have to filter out manually in their code).

See e.g. http://stackoverflow.com/questions/4665244/system-in-a-collection-name-in-mongodb?rq=1