A recent article in The Economist magazine warns of a nascent bubble forming in high-tech company valuations. An initial public offering by social media site LinkedIn raised twice the amount of money projected -- and excitement is growing about expected public offerings from Twitter, Zynga and Facebook. But many pundits disagree.

Host Michael Krasny and the Economist's Martin Giles scan the horizon for signs of a bubble.

• More: Read the article "The New Tech Bubble" - at Economist.com