https://www.bitcoinplus.org/blog/bitcoinplus-xbc-v270-rc1-releasedFirst major release since 2.6 which incorporate many changes the most note worth of which are listed below. This release is based on Bitcoin 0.13 which has all the latest soft forks, the previous release was based on Bitcoin 0.7.
BIP9 Version Bits which starts on block 2120000
Segregated Witness BIP9 Soft Fork
Elimination of unwanted transaction malleability
Capacity increase
Weighting data based on how it affects node performance
Signature covers value
Linear scaling of sighash operations
Increased security for multisig
More efficient almost-full-node security
Script versioning
CHECKSEQUENCEVERIFY BIP9 Soft Fork
CHECKLOCKTIMEVERIFY Legacy Soft Fork
Faster synchronization
Hierarchical Deterministic Key Generation
Dynamic transaction fee
RPC Access Control Changes
-rpcallowip=192.168.1.* becomes -rpcallowip=192.168.1.0/24
-rpcallowip=* becomes -rpcallowip=::/0
REST interface with -rest flag
Watch-only wallet support
Block file pruning
Memory usage optimization
Reduce upload traffic
Direct headers announcement
Notifications through ZMQ