WSJ.com thought it was pretty clever when it launched an ad camapign called Biz-O-Rama mocking its free counterparts. But The New York Times reports that the Journal appeared to have lost its sense of humor when MarketWatch tried to place an ad on The Journal Online that asked, in a preliminary version, “Where does The Wall Street Journal advertise ? when they need to reach the online business audience?” The ad’s answer: CBS MarketWatch. Dow Jones not only rejected the ad, but then pulled its Biz-O-Rama ad from MarketWatch.com. The curious will be able to find the ad next week in the online and print editions of Advertising Age.