- Microtransactions.
- Transactions cost nothing.
- Anonymous
I disagree partially with all of these points.
Bitcoin isn't completely anonymous, unless you go to some effort to launder your money. Anyone can look at the block chain and trace the addresses a particular coin has passed through. And sometimes from this, and from the times and amounts and any other useful information you might have, it's possible to guess things about where the coin came from and what people did with it.
Transactions don't cost nothing. At the moment most of them are free, but it's certainly not a "core idea" of Bitcoin. Very small transactions or very complex ones won't be processed without a fee. In the future, the fee structure could be very different, as the reward from mining will be a lot smaller without fees.
The Bitcoin protocol itself won't be useful for micropayments if it's widely used, because it's not very scalable (every node in the world receives every transaction in the world), it's too slow (it can take minutes or sometimes more for a transaction to be confirmed at all, and longer if you want more confirmations), and because transaction fees will probably rise in the future. Micropayments aren't a "core idea" of Bitcoin.