well sure it does... the more people that use bitcoins then the more demand there is for bitcoins. the more demands there is for bitcoins the less supply there will be. the less supply there is the higher the price is.
Actually an increase in demand will simply lead to a higher price. No need to worry about the supply curve as long as it doesn't shift (of course there is a marginal shift of 25 BTC per block but I wouldn't worry to greatly about that in the short term).