Email has a huge spam problem. I wonder whether bitcoin will also be weighed down by spam in the future. Maybe satoshidice is just the start. We'll have an avalanche of micro transactions that take the blockchain to terabytes in size.
I expect micropayments to become commonplace.
Right now with credit card processing, it isn't practical to run a service that thrives on micropayments.
Remember in the 80s when we use to put a quarter in the video game slot? Those were micropayments and people got rich off of them. But that's not practical on the web due to processing fees.
bitcoin solves the problem. I can pay 2 mBTC to read a news story or 5 mBTC to play a game or whatever and the .1 mBTC transaction fee doesn't hurt me.