This could impact banks with a huge exposure to mortgage-backed securities and low overall securities yield. Despite these concerns, Penala still expects buybacks to triple in 2013, with JPMorgan Chase ( JPM) and Citigroup ( C) poised to return $4 billion and $15 billion next year. Among the regional banks, Regions Financial ( RF) and BB&T ( BBT) are her top picks. These banks might ask for debt extinguishment, boosting net interest margins and earnings power. -- Written by Shanthi Bharatwaj in New York.