Hot on the heels of its spectacularly oversubscribed IPO, Alibaba has officially launched the first Chinese ad exchange, Alimama. The wraps are being taken off Alimama after a 100 day beta.

“No longer will 80% of China’s website traffic go unmonetized,” said Jin Jianhang, an Alibaba Group spokesperson. “The launch of Alimama makes web publishing commercially viable for China’s more than one million small- and medium-sized web sites. At the same time, advertisers now have an affordable way to reach targeted audience groups on the growing number of specialized websites and blogs in China.”

A press release on the launch says that Alimama has already built a network of over 150,000 small- and medium-sized web publishers plus 135,000 personal blogs, and growing by 4,000 sites and 10,000 blogs a day, for a total of over a billion page views per day. Not a bad lot of inventory! Advertising transactions are happening at a rate of 20,000 per day. The release goes on to say:

Alimama’s unique business model is designed to meet the needs of China’s fragmented market for online advertising, providing a system that is transparent to both web publishers and advertisers. To use the service, publishers register on Alimama.com to provide a description of the advertising inventory for sale, as well as the pricing models based on which the inventory can be sold, such as pricing based on impressions served, clicks or other actions by Internet users. Advertisers review the information posted by publishers, along with independent website traffic data. Once they’ve decided to buy the inventory, they simply click ”Purchase” and follow the steps to upload their ad. Current advertisers include large companies such as Bank of China and small advertisers, such as restaurants and shops.

Sounds a lot more primitive than the more fully-realized ad exchanges in the U.S., where instant auctions are carried out. There’s no indication of that here. And it sounds like there’s quite a bit of work invovled on the part of advertisers, who–judging from the description in the release–have to sift through an awful lot of publisher and traffic data to find inventory they want to buy. Exchanges like AdECN or Right Media are quite different: Advertisers need only specify what types of individuals they’re trying to reach, and how much they’re willing to pay per mil/per click/per action.

Has anyone out there used Alimama yet? I’d be very interested in hearing your feedback.

Hat-tip to China Tech News, where I first spotted this.