The Bitcoin Core development team released the newest version of the main Bitcoin implementation, Bitcoin Core, on July 12. Bitcoin 0.11.0 includes several improvements over older versions, making the software easier to use and better adapted to current network needs.
One significant addition to this latest release of Bitcoin Core is the option of block file pruning. In essence, this allows users to rid their version of Bitcoin Core from all data included in older blocks that aren't necessary to run a full node. As such, it is no longer needed to locally store the full blockchain, but instead limit this to (a minimum of) the latest 550 blocks.
This comes in handy for users with limited space on their hard drives, as the full blockchain is currently nearing 40 GB in size, while the latest 550 blocks can be 550 MB at most. It should be noted, however, that block file pruning is not yet available for users of the Bitcoin Core wallet software — though it will be in future releases.
The newest version of Bitcoin Core also includes an improved fee-estimation mechanism. This means that users will be better able to add the correct amount of fees in order to have their transaction processed quickly. To accomplish this, Bitcoin Core 0.11.0 scans the mempool — all unconfirmed transactions — and the latest block in the blockchain to estimate how high a fee needs to be in order to be included in the next block.
In light of recent spam attacks on the Bitcoin network, and a possibility of blocks being filled up with genuine transactions in the future, such mechanisms will be helpful to establish a functioning fee market.
Bitcoin Core 0.11.0 includes improved privacy functions as well, in particular because it connects to the anonymizing TOR network more effectively. If TOR is enabled, the newest Bitcoin software uses different TOR circuits to connect to different peers, as opposed to one and the same TOR circuit. By diversifying the number of TOR circuits it connects to, Bitcoin Core now significantly reduces the chance that users get unlucky and pick a single exit node that is either malicious, or widely banned from the P2P network.
Other changes in the new version include better performance and memory usage, and additional user-specific privacy improvements.
Bitcoin Core 0.12.0 is expected to be released in about six months.