The idea is to decentralize even more by making the technology easier to use by a wider audience. A BTC blackbox, a BTC credit card etc (or rpietila's paper BTC IOUs - hmmm like Ripple ) are what's needed.
We need to take the geek side out of the Bitcoin use. Make it easy to use so people can simply ignore the technology behind it and use it as they would any other currency (and each device should be a miner, to process transactions and secure the network). That's when mass adoption can really start.
OTOH, I also think that Bitcoin will be superseded, eventually, and possibly even by a GOV-launched coin (best way to beat BTC is to make it irrelevant), unless we reach critical mass within a short period of time (less than 10 years from introduction).
I can't imagine people would happily adapt some coin created by governments.
The founders of a company are usually able to grow it to a certain size. The you need new people, "the suits", to grow it even bigger. It's like people are stuck within a certain 1-10 factor. If you want to reach 100, you need new people at 10.
Bitcoin is the founding coin, who's to say it'll grow enough before it runs out of steam? (maybe Bitcoin 2.0 will be the next Bitcoin, I'm not discounting the possibility)
but these new coins can partly be exchanged to each other already.
I'm sure coin market would transform and every btc holder could change it to the new rising cryptocurrency. you can't just leave btc market out and start from the beginning creating your own.
(except you are a big company with an already huge market share)
the comparison to social networks was a bit off by me because some user account is worth nothing for a market in itself than the potential for marketing, btc has an actual value to buy products and that can't be ignored.