It's an interesting idea to have a coin that is backed by something that has real tangible value in the industry (storage space)... I'd like to know whether or not the intrinsic value behind Filecoin (in terms of $ worth of storage space) will be worth the cost of operating the network (in $ terms).

As a buyer of storage space, if you need storage, isn't it always going to be cheaper, faster and more convenient to use your own hard disks or a specialised service like S3?

Will people actually have an incentive to use Filecoin as a storage service instead of S3? If they don't, then the coin has no advantages over Bitcoin.