Yahoo has taken, as promised, steps to open up the architecture of its popular website. The latest one is opening up its address book, a feature which was requested for a long time by developers. Yahoo says that there are about 500 million address books on its servers, which amount to billions of records.

Last month, Yahoo made changes to allow developers to use its search results in a more flexible way. It appears that the company, fresh after deflecting a buyout bid from Microsoft, seeks to reform itself for the new market conditions.

Chris Yeh, head of the Yahoo Developer Network, told CNET News that there will be more such changes soon. The moves are part of the so-called Yahoo Open Strategy that Chief Technology Officer Ari Balogh announced in April this year.

A few days ago, Jerry Yang, Yahoo's brilliant CEO who is under fire from greedy shareholders, has dismissed allegations that the portal company is in trouble. Yahoo President Susan Decker was at Yang's side, explaining that the company was reorganizing around four pillars: home page, search, mail and mobile services.

Meanwhile, greedy shareholders such as Carl C. Icahn, the billionaire investor who recently bought 50 million Yahoo! shares, are trying to replace the company's board which supports Yang and his decisions.