Yahoo Bursts Bubble on China Forecast     Topping tonight's high-tech highlights, Yahoo gives a reality check on the e-boom in China. The U.S. Internet portal says that near-term growth prospects for China's Internet development are . Instead of current forecasts pegging online advertising spending in the mainland at 60 million dollars next year, Yahoo claims that 35 million dollars is more realistic. Barriers to China's online explosion, unclear overseas ownership rules, low quality local content, market volatility and inadequate telecom's infrastructure.