As of now, Server 3 is open for new registrations. There are no changes compared to S2 in troops or buildings stats or costs.

Server 3 will be launched on January 19th, at 13:00 server time (11:00 AM GMT). As of now registrations on S2 are closed. If there are any bloggers playing the game, we’re offering 3 months of free VIP for anyone that announces the start of Server 3 on their blog. I’m talking about established blogs [...]

As the title says, the Gunpowder Age has been launched on S2. You can upgrade to the second age from the Gunpowder Age tab in the City Hall. Requirements: City Hall lvl 20 at least 2 villages at least 600 population 30,000 for each resource plus 10% of the training costs of all the military [...]