According to the Bitcoin white paper, it was designed for "small casual transactions" that are too costly with conventional trust-based online payment methods (e.g., Visa, Paypal, etc.)
source: https://bitcoin.org/bitcoin.pdf
...I really don't see how you're still trying to fight for including all of the world's transaction on the blockchain when there is consensus among pretty much all the qualified engineers (that would include Gavin although I'm increasingly doubtful about his qualifications) that a POW system is simply not able to efficiently service this type of load/transactions….
I don't believe the Blockchain will be useful for sub-penny micropayments (for example); I like the idea of payment channels for that.
The point of my post was to show that @manselr was correct: Bitcoin was designed for small casual online transaction that are too costly with our present trust-based model. Whether it continues to meet that design objective, the truth is that no one knows. Will the threshold for direct Blockchain access be sour-candies from 7-11, Xboxes from BestBuy, or something else?