What I find odd about this is that there does exist at least one perfectly fine micropayment system. It's running in my laundromat (the company is Heartland Micropayments), where I can use my credit/debit or laundry payment card. When I wash and dry three loads of laundry, I don't get 6 charges on my card. I get one.
It seems like it wouldn't be a huge amount of work to bring this to the internet, particularly since it's using the internet for its communication in the first place.
Batching small payments is not the hard part of creating a payment system that can support the entire Web. Harder parts include problems like UX (e.g. balancing the need to make a system people will want to use against the danger of users unknowingly running up a huge bill), getting buy-in from websites (why should they use your service in particular?), and just convincing people to sign up for yet another godforsaken account on the Internet.
It seems like it wouldn't be a huge amount of work to bring this to the internet, particularly since it's using the internet for its communication in the first place.