Okay, Google, watch out. I was underwhelmed by Facebook’s last big advertising announcement – the Facebook Audience Network for mobile app promotion. But last week’s Atlas re-launch during Advertising Week is a different story. While Facebook is exaggerating the necessity of an ad server that doesn’t rely on cookies, it is very much on-trend with digital marketing buzzwords like programmatic buying and cross-platform targeting. Google’s DoubleClick empire is officially under siege from a well-armed horde.

What it means

Google and Facebook are Numbers One and Two in the $140 billion digital ad market, though Google has three times Facebook’s market share. Facebook has been rapidly closing the gap in the $30 billion mobile segment. Each makes most of its money selling its own inventory, but Google has a big business in ad networks and exchanges for placing ads on other publishers’ sites. Facebook has still only dipped its toe into ad…