I couldn't really tell because the games were in Best Buy's security cases.
This is a promo mock-up version that Working Designs made, but wasn't used for the game's release. I remember seeing Vic Ireland (either it's him or some other former WD employee) selling it with explanation in an ebay listing.
*edit*I found a finished listing for one here: http://cgi.ebay.com/ws/eBayISAPI.dll...m=140193250669
I can confirm from my copy that the disc simply has SLUS 20347, as does the spine. There isn't any P following the SLUS number on either. The only distinctions seem to be that the cover and instruction book cover both say "Promotional Copy Not for Resale" and the different UPC number.