This is a good, old-timey, dot-com kind of day for Silicon Valley and Wall Street, this whole Facebook IPO business. Suddenly, the hoodie is as iconic as the mock turtleneck. Suddenly, we're talking about 20-something millionaires again (and billionaires) and what they're going to do with all their money.

Wall Street's been priming this pump for months. If you think trading in Facebook shares is going to be frenetic when it begins, around 11 a.m., well, you're right.

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