Here is what we know so far:

* Game Servers will not be released until right around midnight. Expect to spend some time for unranked. Ranked should be quick.
* A RCON Tool w GUI will be released with the game
* 18 Player Max for Ranked
* 24 Max for Unranked
* Custom Server Banners are supported
* -Built-in RCON functionality, very cool!
-Server messages / MOTD (& banner?), check!
-Kick & ban
* Wager matches will ONLY be hosted by Treyarch and allow 6 People Max
* No Nades for First 10 Secs
* Hardcore mode

more here: