[lukifer]

In theory, applications can be built on top of the existing BitCoin blockchain, which is now well-guarded by many vested interests; some projects like MasterCoin [1] and Colored Coins [2] are attempting to do just this.

But ultimately, you are correct: bootstrapping a new blockchain-based service requires assembling a community with enough hashing power to fend off 51% attackers. Time will tell how the experiment will pan out, but even if most projects fail, my gut is that at least a few will succeed in the long run.

[1] http://www.mastercoin.org/

[2] http://coloredcoins.org/

[spiderbro]

Don't forget Counterparty [3]

[3] https://counterparty.co/

[dragonwriter]

> In theory, applications can be built on top of the existing BitCoin blockchain, which is now well-guarded by many vested interests

"Presumed to be well-guarded by many vested interests". Of course, if you don't know who controls how much of the network, you don't know that its guarded by anything, or what the vested interests with influence over the security of the blockchain are actually interested in.

[StavrosK]

Does anybody know how on earth Bitcoin is supposed to scale in X years, when everyone needs to have every transaction ever made stored on their computer?

[lukifer]

It's an implementation detail. Currently the reference wallet stores all transactions, but future versions will be able to prune old blocks and rely on more recent "reference blocks" as their starting point.

[StavrosK]

That's interesting, thanks.