According to The TV Addict Bonnie~Katerina Graham is next in line for a family reunion and Bonnie's witchy relative may be in Mystic Falls as I type. In true TVD style the new arrival has her own agenda and is said to have a sordid past with Katherine.
Who does that sound like to you? My guess, and it's only speculation, is Lucy~Natashia Williamson. If you remember in "Masquerade", Lucy promised Bonnie that she'd see her again. What are your thoughts on this new piece of spoilery goodness?