Treyarch's Community Manager, Josh Olin, has announced through his Twitter that there will be a Double-XP event taking place this upcoming weekend for https://www.trueachievements.com/Call-of-Duty-Black-Ops....htm
Josh Olin, or JD_2020 as he goes by on twitter, had "always wanted to tweet entirely in hashtags". So in his attempt, the Double-XP Event was revealed:
#CODBlackOps #DoubleXP #ThisWeekend #AllPlatforms.
A Hashtag tweet results in a Double-XP Weekend? Fine by me!
The Double-XP weekend will begin at approximately 10am PST on Friday, 4th March, and ends at the same time on Monday, 7th March. Enjoy.