A trick Gladwell frequently uses (not unique to him, of course) is to use insider jargon to make you feel like you know something that only experts know. For example, if not for Gladwell, I would not know that diaper developers call the spill they are called upon to absorb "the insult." And if not for an early-90s issue of Car and Driver, I would not know that automobile designers call the way a car's finish changes appearance as light moves across it "travel" (except at IIRC Ford, where they call it "flop").
Also, you can boil down a lot of engaging non-fiction to finding a narrative and hanging your facts onto it. In stories of scientific progress, for example, there are obvious narratives: mystery, a sense of the secret being revealed bit by bit. This works even though the people who discovered or invented the individual pieces might not have been aware that they were working toward the goal; as the writer, you pretend that progress is inevitable, and omit all the facts that don't lead to your thrilling discovery simply because they're not part of the story. Take particular care to note the roadblocks and how the participants in your story overcame them, or better yet, how a roadblock stopped someone cold but the thread was later picked up by someone with a fresh perspective. Dig for the tantalizing hints that correlation is causation (this happened, then something else happened, therefore the first event caused the second) and that there is some kind of grand plan, if only humankind's collective unconscious, behind it all.
There's a smug aphorism to the effect that "writing fiction is harder than writing non-fiction, because fiction has to make sense." In reality, non-fiction has to make sense just as much: readers want to understand the motives of the murderer as much as they want to hear the lurid details of his crime. Your job as a non-fiction writer is to turn ordinary people, some of whom may be quite boring but who nevertheless play pivotal roles, into compelling characters, while not neglecting the facts. You must make the whole story hang together in a way that real life does not (including a satisfying sense of closure at the conclusion)... while remaining true to reality. It is a difficult line to walk successfully, and surely not every real-life story is suited to such treatment, so selection of your topic is also important.