Yes - include NG. I subscribe to NG, and a good chunk of the covers are portraits, picks of animals, etc.
What about creating the category so it is similar to the "Photos: Now and Then" or the "Ansel Adams" categories? The photo you take of the place would need to be taken from the same (or nearly the same) spot. Just a fun twist, and easier for officers to know that it's the same spot. I think Opinionate may have suggested this earlier in the thread, but can't remember. If he did, he got the idea from me. 
And no, taking a photograph of a magazine cover is not a copyright issue. I think that our friendly, Canadian copyright specialist posted something about photographs of art, etc. on another thread about that.