parroting agricultural enterprises' propaganda?
World hunger is caused by the large amount if grain and soja used by animal live stock. If eaten directly instead *that* would be a lot more efficient.

Everyone has everyone's data, but the data is encrypted and pseudo-anonymous - meaning you can't get information on someone's transaction without knowing a long bitcoin-address. The latter you can recreate for each transaction for added security. For more information, use a search engine like this one: https://www.google.com/search?q=bitcoin+introduction

What makes the encryption/privacy issue for BItcoin easier is that the data that is stored are just numbers with little or no value on them own: data like 1235.12 is absolutely meaningless when you don't know to whom and what the number applies too But data like a JPEG representing a cat or a text like 'I dated with Alice' already means something on its own.
So our distributed social network would have to store only data of each-other friends. When you use Facebook or similar social networks, it stores data of *everyone*.

A distributed social network without any central server would certainly work: just look at Bitcoin.
When you start up the Bitcoin client, you can securely transfer Bitcoins to other clients. The Distributed social network client would instead of transfering Bitcoins, transfer social information (pictures, messages). Instead of replicating transactions as Bitcoin does, it could replicate the state of all of the connections ('friends') of the person running the client. That friends could replicate the state of the person as well, so when you'd have enough friends you wouldn't have to worry about backups.

Oracle joined the Eclipse foundation reluctantly and they have, as far as I know, not released an IDE based on Eclipse.

JDeveloper is more targeted for RAD development or development for software to run on Oracle software (such as JHeadstart) - although JDeveloper is certainly not limited to Oracle software. By the way, JDeveloper is based on a old version of JBuilder (I think it was JBuilder 2)

I, as many programmers, like Netbeans more then Eclipse, so changes are big Netbeans will get (more) support of Oracle.