When the networks bubble over

[Commentary] A get-rich-quick atmosphere is enveloping Silicon Valley at the moment, with Wall Street investors competing to buy privately traded shares in social media companies such as Facebook, Twitter and their imitators.

It has a mysterious newcomer in Color, a photo-sharing application for mobile devices that has puzzled many users but which easily raised $41million – several times the usual amount – in its first funding round. As Color launched last week, the veteran investor Warren Buffett spoke out about social networks, declaring: “Most of them will be over-priced ... Some will be huge winners, which will make up for the rest.” Buffett has long shunned technology companies as having uncertain prospects compared with the insurance and food and drink companies he prefers, and he is right about the latest craze.