From China Digital Space
SB会 (SB huì): SB Conference
In Chinese, the World Expo is called the 世博会 (shì bó huì), literally “world expo conference.” The initials of the first two characters are SB. Coincidentally, SB is a common online abbreviation for the Mandarin profanity 傻屄 (shǎbī), which translates literally to “stupid cunt.”
The 2010 World Expo in Shanghai has been controversial due to its enormous cost (the government spent more on the Expo than it did on the Olympics in Beijing) and to the relocation of local residents who allegedly received inadequate compensation. Netizens claim that the government will profit greatly by reselling the land after the Expo when the pavilions are demolished and the land is cleared. Some  netizens who expressed views critical] of the World Expo found themselves invited to “drink tea,” a euphemism for being interrogated by security forces.
Some Shanghai residents were angered by government efforts to restrict them from wearing pajamas ouside of the house, a longtime Shanghai tradition, so as to put on a good face for foreign visitors.