I have a 2010 MacBook Pro and it's about 10-20% better battery life.
Mavericks IMHO is designed for the newer MacBooks which really need to get to 8+ hours battery life for it to change people's behaviour i.e. being able to realistically leave the power adapter at home.
Mavericks IMHO is designed for the newer MacBooks which really need to get to 8+ hours battery life for it to change people's behaviour i.e. being able to realistically leave the power adapter at home.