Programmatic ad spending should hit $12 billion this year, with the U.S. accounting for $7.5 billion, according to eMarketer, citing an October Magna Global report. Estimates put spending at $32.6 billion by 2017, with about $16.9 billion allocated to the U.S. Real-time bidding -- which is one form of programmatic buying -- will reach $3.3 billion in the U.S. in 2013 and see double-digit growth rates through 2017, about $8.5 billion, per eMarketer.