Well, is the point of Ethereum to make some cash at the expense of later investors (basically a Ponzi scheme), or does the platform have some intrinsic value? Point is, the platform itself can be duplicated at little cost (it's an open source project after all, just fork it), so the cost to the (new) user should be low (or more importantly, stable), even if the value proposition is high.
This logic leads me to conclude that almost all the value of Ether is purely speculative and could disappear at any time.