Sarah Lacy asks the question, that Walt Mossberg should be embarrassed for not asking:
>So if it’s so great, why only 600 advertisers?
For the record, Mossberg decided to respond to the 600 advertiser number from Twitter CEO Dick Costolo with the following:
>Echoed Walt Mossberg, it’s “the perfect wet dream of every marketer.”
*Walt Mossberg: asking the tough questions… wait.*