It may just be an incredible coincidence but every time I've played there's only been a select 3 or 4 items spawn and re spawn each match, only a noticeable few and never the whole range of items.
E.g. some matches I just get RPG, Wipeout Shield, Spear of Destiny and Airstrike gun spawn all match and nothing else. --- I'd rather spend my life close to the birds than waste it wishing I had wings. Also: http://www.youtube.com/user/selite?feature=mhee