Elad Gil has posted some good analysis, trying to answer the question:
Are We In The Inflationary Part of an Internet Financing Bubble? 2011 = 1997 (?)
Elad points to a quite number of similarities (as well as a number of differences) between this period and the late 90s, and comes to the conclusion that yes, the signs indicate that we are getting into another bubble, though the amplitude of it, this time around, is yet to be determined (for example, it may not spread all the way to the IPO market, like the dot com bubble did).
It's worth adding, also, that at the moment this bubble seems mostly located in the US, and largely in Silicon Valley from what I can tell. Over here in London, the investment climate is still frigid.
So, are we in a bubble? Well, the old wisdom says that you know you're in a bubble when everyone believe there isn't a bubble. When the bears join the party, it's about to pop. Conversely, when everyone gives up hope, things are about to go back up. So are we in a bubble? The number of arguments that we're not in a bubble does seem to be rising. My guess is we're not there yet, but it's likely on the cards for the next few years. It will probably take longer than the 24-36 months Elad suggests, though. IPO season has only just started, after all.
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