The original Black Ops multiplayer trailer was released on 9th of August, 2010 and now it seems that the Black Ops 2 multiplayer reveal will happen almost exactly 2 years later. The official Call of Duty Twitter account has just tweeted that the Black Ops 2 multiplayer will be revealed on 7th of August.
@CallofDuty: "In just 4 days, we reveal #BlackOps2MP. RT if you’re ready to see Multiplayer in action."
It has also been speculated that the Black Ops II multiplayer will be playable at the August gamescom 2012 trade fair since there won't be a Call of Duty XP this year.