RightAsRain,

You are absolutely correct in your articulation of the use of the CC license you describe. Because there is so much confusion about CC in general, and the application of each license type in particular, it is always best to treat each and every instance of secondary use of your work on an individual basis, i.e., issue a specific license for each specific usage. Open Source is not always "Open Source" either, so don't get confused by that (you can have conflicting licenses there) ... unfortunately, there doesn't really seem to be a single "Open Source" definition (which is why I never refer to my works as being open sourced) The CC license can be as inclusive or exclusive as you wish to make it and again, you may issue multiple licenses for a single work.

Technically, people can only do what they have been specifically granted to do in SL ... you, the creator, have complete ownership over what you create. HOWEVER ...

...all of that really only applies if YOU have created everything in your piece. If you use anything created by anyone else, you really need to have permission to do that (note that when you look at an object's properties it will list both an Owner and a Creator ... that's what I'm referring to here...).

Sorry if it seems like I'm hammering away at it, but as Otenth pointed out, even in our own backyard we have made some grievous oversights that should be corrected.