how many people play texas hold em
how many people play poker
how many decks of playing cards are sold every year2004 compared to 1999

Question #2:  How many people play poker?

The following was copied from Hold'em Shirts and Gear
(www.HoldemShirts.Net), in an article written by Phil Gordon:

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Jeopardy Answer: 50 to 80 million.

Jeopardy question?

(a) How much money has Phil Ivey won in cash games in the last few years?

(b) How many Americans identify themselves as poker players?

(c) How many hands are dealt in on-line card rooms on a daily basis?

I'm not sure if (a) and (c) are true, but (b) is a lock. 
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