An article at the Guardian asks whether the exceedingly high valuations of social tech companies signify the arrival of a second dotcom bubble
"Every week, one of the new generation of internet firms seems to attract a sky-high valuation. Zynga, the social-network games company that has tempted millions to grow virtual vegetables in its FarmVille game, has been valued at $9bn (£5.54bn). Profitless Twitter is said to be worth $10bn. Groupon, vendor of online discounts, rejected a $6bn offer from Google and is considering a flotation with a potential valuation of $15bn. Tech-watchers say this is just the start: the real boom will come when Facebook, the head boy of the new dotcom frenzy, goes public, probably next year. ... The last dotcom boom really took off after the flotation of the internet software company Netscape in 1995. Patrick says this time it's likely to be Facebook that lights the fuse. So far, private investors have been locked out of the New Thing. But JP Morgan is setting up a fund, and Goldman Sachs recently tried to get its clients' money into Facebook."