OPs question is what i'm asking myself for a couple of days now and i've found no reasonable explanation yet, besides "BC is teh future!".

Exchange rate is fluctuating extremely and is too easily influenced by lots of factors right now, which makes it a pure gamble to accept bitcoins for goods that you've payed real money for, imho.
Bitcoin exchange rate needs to be somewhat stable, before i'd personaly would accept them as a payment option. You never know what they will be worth the next hour/day.
Playing around with the money on the exchanges is something for banksters, not merchants. At the end, as a merchant, you've payed real money for the goods you sell and you have real bills to pay.
What am i missing?
