So why do the paperback versions of a $15 hardback book generally cost $7 - $8? Paperbacks as well as Hardbacks still need all of the above support personnel you speak of. At $9.99 Amazon is STILL coming in above the paperback price of most books.
I'm sorry, but the arguments that Scalzi puts forth above are absolute shit, and you have the hint of schill about you. There is no reason that the electric format should cost anywhere near the cost of a hardback. Hell, IMHO the electronic format should really be below the paperback price because of the lack of dead leaf being used for its production... but I can understand the industry's desire to hold on to their model and I feel, much as Amazon seems to, that $10 is a reasonable compromise.
If they REALLY want to milk the consumer they should use a similar model for E-books that they use for paperbacks; as in, release the first edition hardback at $15, wait a month for sales to start becoming stale, then release the paperback and E-book at the same time at the reduced rate.