I know there is a limited amount of true wealth in the world and that gets diluted by the number of active investments in the world.
Bitcoin has gained it's value by being magnitudes more efficient, and soon much better designed than the banking system that it will replace; This is why it is appreciating in value, the people see what it is worth and are rallying their economic power around it, they know it is better, too long has the technological potential of our minds been held back by ancient obsolete systems.
This is where Bitcoin is getting it's wealth from, it's simply a better way of exchaning wealth.
The Alt-coins have limited potential simply because they are the same as Bitcoin, only small improvements or worse. The time and effort required to move to them would require another advantage that will have to be determined for that particular coin. It will gain a little wealth, but it must start at zero to assess it's value properly.
so I as well cannot determine where the wealth of these coins is coming from, A POW advantage can attract a specific type of person to complete the human challenges.
Devcoin is a great start, but it is definitely very badly executed, bad interface, limited scope for it's mission, not diverse enough, no place for it's members to congregate and exchange ideas more effectively, but someone will figure it out.