SHANGHAI/HONG KONG: Baidu's hasty move to a new Internet advertisement system marks a rare stumble for China's dominant search engine, opening a window of opportunity for others salivating for a piece of the country's fast-growing online market.

Baidu, whose name is practically synonymous with Internet search in China, surprised investors when it revealed transition to its new Phoenix Nest system will lead to softer revenues into next year as customers adjust, sending its stock down sharply.

The news was music to others, such as Sina Corp and global search leader Google, looking for a bigger piece of the pie in the world's biggest Internet market with 235 million search users in June, up about a third from a year ago.