Basic questions:
1. Where is the data stored? How much redundancy? Obviously you need data to serve content.
2. How do you ensure that users are actually serving the correct data?
3. How will you validate the amount of data being served? (Imagine that an attacker controls both sending and receiving nodes. It would be trivial to fake the amount of bandwidth "used").
4. What types of data will you disallow? (This has many important legal consequences, as I'm sure you can imagine.) If everything is "allowed", I'd imagine most users unwilling to participate in fear of lawsuits/retaliation/subpoenas.
5. What is a "coin"? (unit of storage/bandwidth?) What is "difficulty"?
I've been working with Liberman on a lot of the basic concepts, but I don't understand how some things will work technically.
1. Data is stored in nodes (the "miners"). The system is being setup so more nodes host the most popular content. The amount of redundancy depends on the popularity of the content.
2. Users will interact with Bitcloud in a client where they basically search through the files that are approved by a moderator. The moderator will have a list of files that its nodes store locally. I assume some form of verification mechanism can be used to make sure the node's files match the moderator's list.
3. Nodes cannot cheat the system because there are multiple nodes sharing the same file. The node that the user connects to is chosen at random.
4. Everything is allowed on the unmoderated system that will work on an anonymized layer, similar to Tor. On top of that, moderators will be able to set guidelines for content uploaded to their nodes. A node can choose to follow a few different moderators or simply allow unmoderated content to be stored on their server.
5. The coins represent bandwidth. A block reward is given out every 10 minutes. The block reward is distributed to all nodes. The node's share of the block reward depends on their share of the total bandwidth used by Bitcloud users.
Edit: Decided to go ahead and answer number 3.