For technology executives weighing market flotations for Silicon Valley startups, this week’s gangbusters Twitter Inc initial public offering sent a powerful signal: full speed ahead. About a dozen private companies are valued at more than $1 billion and many of them have already been holding informal talks with bankers with a view to accelerating their IPO plans. File-sharing company Box has picked Morgan Stanley, Credit Suisse and JP Morgan to lead its IPO. The company has been valued at more than $1.2 billion by private venture capital investors but it remains unclear whether it is profitable. Twitter’s lack of profits proved to be no obstacle to the micro-blogging site raising as much as $2.1 billion in its IPO. That opens the door for other big-name private companies including Square, the payments company founded by Twitter co-founder Jack Dorsey which has begun exploring the possibility of an IPO next year. Profits are not expected until 2015. Airbnb, an accommodation service, is also often cited as a potential IPO candidate. “They don’t have inventory and have pretty low overhead,” said analyst Michael Pachter, who believes the company is profitable. Social media service Pinterest, meanwhile, raised $225 million at a $3.8 billion valuation in October even though it had only begun to make money in September by showing ads. Snapchat is perhaps one of the furthest down the line. Used by 9% of U.S. mobile phone users, Snapchat raised $60 million earlier this year at a valuation of $800 million. The market’s embrace of Twitter comes right as the IPO market enters what is typically a seasonal lull around the time of the Thanksgiving holiday and do not really get started again until February or March. With many in Silicon Valley believing that the appetite is growing for tech IPOs, there are a number of similar companies also taxiing along the runway ready for take-off. Watch this space!