In actual fact, generic terms and numbers cannot be TradeMarked(TM)...
Take the case of Windows and a Linux distribution, Lindows. Microsoft tried to sue the creators and districutors of Lindows for the 'blatant' infringement of the 'Trade Marked' Windows OS... the court deemed the term "Windows" too generic and, therefore, threw Microsoft's case out the Window...
Same goes for numbers... That is why Intel decided to name their processors Pentium(from the term penta- which means 5, like pentagram etc...) after their 486 line of processors(from 286 to 386 to 486 and the planned 586, get it?) so that they can Trade Mark the name. Which makes it more difficult for 386, 486, Pentium clone manufacturers to use Intel's product line to advertise...
But for this situation... it's just wierd to attempt to copyright and/or trademark a term which consists of 2 very generic terms(costume and playing...)
