is a tweet like two punched cards?

I know there's actually 80 columns to an old IBM punched card, but I somehow think of a maximum tweet being like two punched cards.

On the old punched cards, columns 73-80 were for sequencing and 72 was reserved to signal that a continuation card followed. So pragmatically 70 characters per card, or half a tweet.

So I've always sort of thought that twitter has harnessed a short messaging platform for chatter using a maximum message length of two IBM cards.

So if we treat Twitter as an I.T Company, somehow it's single idea and its ramifications is today valuing the IPO capitalisation of twitter at around $30bn.

That's between a quarter and a third of the total market capitalisation of IBM ($117bn).

Or if we treat Twitter as an advertising and media organisation, its market capitalisation is about double that of BSKYB ($14bn).

Hashtag 140 character big business? Hashtag traderorinvestor?