Businessweek has an interesting story this week about the different Web uses – one on the “big” screens of laptops and desktops and the small screens of PDAs like BlackBerry and the iPhone – and the difference between weekday and weekend usages.

The stats show that people’s habits change away from Google and Yahoo! when they are searching for information on a portable device. The story reports that “The fastest-growing mobile-Web categories relate to weather, entertainment, games, and music.”

Clearly, for product publishers and affiliates, this presents a business opportunity – what is the next generation of products and offerings that will appeal to people on the smaller format?