Am I missing something?
But when was 21CN (or any NGN for that matter) supposed to have an impact on data speeds? 21CN is effectively a change to the carrier on the network, and the replacement of legacy voice switches with softswitch's.
For the carrier its supposed to bring a cost saving, due to more capable softswitchs and the IP backbone, both of which improve capability and reduces operating cost as they are a dam site easier to manage then the legacy kit that they are replacing (cheaper to buy, smaller, cooler etc).
What 21CN does allow is abstraction from the physical layer of the last leg, so it doesn't matter whether your coming in on copper, or fiber, or Ethernet, you still have access to the same core services using the same kit (ok the MSAN may need a different card, but its better than a new switch and trans coder). This has two huge benefits (to the customer), 1) all those people that currently have fiber to the door, will be able to get a broadband service and 2) it means that if (/when) fiber to the door finally gets rolled out to the rest of the uk - there is little or no (comparatively) extra cost to the core of doing so.
So what will change...
IMHO, this article should have focused on the thing that really matters, Money! What NGN's really give carrier's is a much more flexible billing and enforcement system - QOS is a means to an end in this. For anyone who has sat through a vendor presentation from the likes of cisco, nortel, ericsson, nokia, etc there is one word that keeps coming up - PROFILE. This is the differentiation of services per subscriber when everyone is connecting over the same network.
Back to money, providing a data service (ISP) makes pretty much no money nowadays (hence why all the small isp's are going under /selling out to BT). The big change - as far a I can see this NGN's will be the selling of services on top - you want VoIP, that will be £1 extra a month, P2P thats an extra £3. 21CN gives the carrier the ability to be able to do this by managing an end user through profiling and its done right at the point where the customer comes in to the network - not as currently - at the point where the carrier peers with other networks, the transmission savings are huge!
I'd say it wont be long before capped /unlimited becomes bronze, silver, gold and then your broadband will be free, if you want to surf, with a fee payable per service that you want to run on top (e.g. VoIP, p2p, video) - just like if you want caller display or voice mail at the moment on your POTS connection.
Just my 2p