DOCBOOK: notes and roles

What tag can be used to make something a future 
reference, or to let the reader know that these features are to be included in a 
future release?

 

I'm thinking a note, but don't really want it to 
say note, ... but I'd like for it to stand out as a note.

 

Also, do docbook tags use attributes, such as role, 
and if so, how?