Lots of new achievements to work for:
Natural Selection - Destroy 4 ships of the same type as your ship or 8 ships of any other type. Successfully complete the operation. Can be obtained once per battle.
Torpedoman - Hit enemy ships with 15 ship torpedoes in a single battle, and successfully complete the operation. Can be obtained once per battle.
Sea Star - Complete the operation and all secondary tasks, survive till the end of the battle and cause damage exceeding 100% of your ship's HP. Can be obtained once per battle.
Universal Seaman - Successfully complete an operation while playing with a ship of each type. Can be obtained once.
Weather Beaten - Successfully complete 50 operations. Can be obtained only once.
Old-Timer - Successfully complete 125 operations. Can be obtained only once.
Experienced One - Successfully complete 250 operations. Can be obtained only once.
Important Missions - Complete 150 tasks in operations. Can be obtained only once.
Special Orders - Complete 450 tasks in operations. Can be obtained only once.
Secret Instructions - Complete 900 secondary tasks in operations. Can be obtained only once.
Exterminator - Destroy 25 key ships and auxiliary ships in operations. Can be obtained only once.
Raider - Destroy 75 key ships and auxiliary ships in operations. Can be obtained only once.
Ravager - Destroy 150 key ships and auxiliary ships in operations. Can be obtained only once.
Shield - Have 20 ships survive in operations. Can be obtained only once.
Guardian - Have 60 ships survive in operations. Can be obtained only once.
Protector - Have 120 ships survive in operations. Can be obtained only once.
http://wiki.wargaming.net/en/Ship:Achievements