I wrote a post in March 2008 about this, still waiting. It would be excellent if in plan we could document where a camera is placed. Sure we can create a family to document where they are but that doesn't provide the automatic view reference that other view annotation enjoys. Seems kind of un-Revity to me, you?
If you decide to create a camera annotation how do you know exactly where it is after you place the camera? Good old "right click" will help, just select the view in the Project Browser, Right Click and choose Show Camera. Make a note of where it is and drop your annotation there.