Skins can have the same name, there's nothing unique about one unless it's trademarked or imitates another persons work.
I understand the trademark, but still a skinner should have the some rights to the name of his widget, gadget, etc I personally don't want people coming out with widgets with the same names as mine. Also you mentioned if the skin imitates another persons work... well DartBoard clock from
NetaholicsAnonymous is very similar to the one I had done.
Out of respect, I would Not call one of clocks 'Foundation Clock' (already done by Tiggz) or 'SD Mini Clock' (done by Vad_M).etc. And if someone already had a clock with the name I gave mine, I would greatly change mine. So I hope there is some middle ground here as to a solution that suits all people.