Online heavy-hitters Google, Facebook, Twitter, AOL (Engadget's parent company) and the Interactive Advertising Bureau have have struck an alliance aimed at ridding nasty advertising "from all corners of the web." Stemming from the existing StopBadware group that began in 2006, the group will develop policies, build a platform for identifying scofflaws and share trends with government and law enforcement. For its part, Google curbed 130 million ads promot