Cadbury Gorillas In Our Midst.

Cadbury Schweppes raised forecasts for its confectionery business, saying that revenue at the division would increase more than 6 per cent this year. In some circles this is already being attributed to the gorilla ad. Well let's just think about some other contributory factors.

Sales of Wispa have grown from zero to 20 million since October.

Trident and Stride gum have gained a 35% US market share.

The summer of 2007 was much cooler than 2006.

The proof of the ad's effectiveness will lie in the performance of sales of Cadbury's Dairy Milk chocolate and that has not yet been itemised anywhere that I have seen. And when they are, we must remember to factor in the inevitable rebound that would have occurred following the rectifying of the summer salmonella incident which led to a 25% slump in sales in June. The relevant comparison for effectiveness purposes will be the sales trend before that slump.

None of this is to say that the ad hasn't been highly effective as well as popular. it's just a reminder that the measurement of any marketing ROI must be done rigorously or we're just deluding ourselves.