It was expected that True Blood's fifth season would return this June, but HBO has now officially announced the date of the season 5 premiere episode:

"The 12-episode fifth season of TRUE BLOOD will kick off SUNDAY, JUNE 10 at 9:00 p.m. (ET/PT). Based on the popular Sookie Stackhouse books by Charlaine Harris, this Emmy®-nominated hit drama series was created by Alan Ball, creator of HBO’s Emmy®-winning series “Six Feet Under.” The show follows waitress and part-faerie Sookie Stackhouse (Anna Paquin), who can hear people’s thoughts, vampire Bill Compton (Stephen Moyer) and vampire Eric Northman (Alexander Skarsgård)."

It has been previously revealed that this season will deal with supernatural elements and will also focus on the Vampire Authority. We've included the recently released season 5 trailer below:

Source: HBO Watch