"Be prepared" is more than just the Boy Scout's solemn creed, or a fun-but-obscure song by Tom Lehrer, the great singer-songwriter-satirist and retired Harvard math professor. It's what marketers should do right now to get ready for the post-modern age of artificial intelligence hurtling toward them.

When it comes to discussing AI technology in marketing, there's a lot of hype. Marketers appear to be in violent agreement that solutions powered by AI will be cranking ROI through personalized customer experiences, better understanding of customer behavior, management of real-time interactions across channels, etc. -but where are we really on the path to cashing in on these promises?

Here are the top four advertising/marketing AI tech startups, according to CB Insights and Fortune magazine.

Often the best way to learn about a new field -- especially one that is both complex and noisy, like AI -- is to watch people who are truly proficient at it. What do they talk about? What do they spend their time working on, and what things do they ignore? Here are five people I have found particularly insightful on topics ranging from neural networks, to self-driving cars, social robotics, natural language processing and AI startup investing. I highly recommend paying close attention to all of them this year.