A double ed’s pick here with some thoughts on online advertising and e-commerce: first figures from Hitwise suggesting that Twitter is driving traffic towards media sites, but not retailers.

“[W]ith one or two exceptions (most notably Dell, which claims to generated $3m via Twitter), very few transactional websites have yet used Twitter to drive sales. During May, Google UK sent 365 times more traffic to transactional websites than Twitter. Given that Twitter has yet to settle on a business model that will take advantage of its huge, loyal user base, this is an issue that needs to be addressed by the people that run the company if they are to make the service a financial as well as popular success,” writes Hitwise’s Robin Goad.

Emerging platform, but no guaranteed financial model (yet) – which leads to a piece from Read Write Web last week on the decline of Google’s AdSense.

The service gained success because it met the needs of publishers, advertisers and users, but now each of these parties is starting to spot problems, writes RWW’s Bernard Lunn.

But, adds Lunn:

“If AdSense is in decline, that leaves open a big market for entrepreneurs. Publishing is not a winner-take-all market. Google will not control all online inventory. Advertisers and their agencies like choice. And users click on whatever is relevant.”

Full .