Exxon's marketplace is largely commoditized, which is part of the reason they act how they do, Apple's marketplace could not be more different.

In particular, oil is a fungible commodity. Fungibility is the key factor here.

http://en.wikipedia.org/wiki/Fungibility

Personal computers aren't a commodity?

Nope. A barrel of oil from Exxon is undistinguishable from any other barrel of oil traded at the exchanges. This is not the case with say, Thinkpads vs Macbooks.

Quote wikipedia: "A commodity has full or partial fungibility; that is, the market treats it as equivalent or nearly so no matter who produces it." So nope, definitely not (yet) the case with computers.

Yet oddly for more the case with "the cloud"

I am hopeful that openstack will give me a large range of providers I can use with the same Apis - and that my app design will be sufficient that even the remaining non fungible parts of a hosted computer (OS, connectivity, size of data stored) will be mitigated

I am not sure if it's a good or a bad thing but pretty soon every computer other than the ones I carry will be commodities