The XOXO Sign is a decoration in FarmVille. It was released along with other items as part of the Valentine's Day Event (2011) to serve the Valentine's Countdown! activity.
It could be obtained by sharing in the Valentine's Countdown!, either by receiving it as a gift from a neighbor or by buying it for 3 cash. Each player can collect only 10 of this item.
Please be noted that the XOXO from previous Valentine's Day Event 2010, wouldn't serve the Valentine's Countdown!, player should seek the "XOXO Sign" for the activity.