Some specialists and investors do not agree. Citibank recently burst a number of potential bubbles, claiming that there was no risk until market indices hit double current levels.

Sun Yu, chief China securities strategist at HSBC, believes that a more open capital market with less government control over IPO pricing means that now is the time for foreign investors to hit China's market.

Not all market rises are bubbles: government policy and national strategy have fueled this rise. Since the beginning of this year, innovation has been the watchword of China's leaders. "Makers" are the new economic heros and "Internet Plus" key to an innovation economy.

According to account registration data, many new investors were born in the 1980s and 1990s, with no experience of the carnage of seven years ago. They are more optimistic and have nontraditional views on investment.

Xiao Wu, an investor born in the 1980s, has an account with Orient Securities in Shanghai. He considers himself expert in technology, media and telecom.

"I am concerned about whether a company possesses core competence and innovative capabilities, or if it has the potential to expand along the industry chain, not profit to earnings ratios," he said.

Some commentators go even further. Yu Weiguo, a columnist at Sina.com, thinks the stock market is set to replace real estate as the new darling of national strategy. A booming market will nourish future backbone industries, he claimed, despite occasional capital bubbles.

"The stock market is a mechanism that encourages innovation. It draws in private capital and helps young people get a foothold in many new industries, some of which could be vital to the transition of China's economy," Yu added.

Another columnist, Xiang Xiaotian, echoed Yu's thought. "For China, if there is no bubble in the second-board market, then there is no start-up, no innovation, and no future for China's economy."