Two words - software engineers. I always say befriending software engineers makes marketing infinitely more exciting. Any marketing trends I've seen are influenced by what engineers were talking about three years prior. Also, adopting an engineering mindset not only allows you to provide better data-driven decisions, but to work more quickly utilizing the latest technology applications. If I can write and run my own SQL queries, know what is the upcoming change that will affect page rank of my clients' sites, or how to work with Google's latest suite of tools, marketing has just gone from "hand-wavy" to scientific in the approach.