Payne's tight, crisp images are certainly eye-catching, and his technical skill stands out among contemporary illustrators.
However, if you get too distracted by the skill you'll miss the larger artistry of these pictures (which is the most important part).
There are plenty of illustrators who do highly detailed, photorealistic work. Artists such as Rowena, Boris and Elaine Duillo are meticulous technicians, but for me their results are usually leaden and uninspiring (unless you count the inspiration that comes from watching honest manual labor). Adobe Illustrator is helping a younger generation of obsessive illustrators take pointless detail to a whole other level.
But Payne brings something more to his pictures. His skill is exercised in the service of a larger artistic vision, which is why his pictures positively glow in comparison.
Note for example his dramatic compositions for these excellent portraits:
Or look at the following portrait of Yogi Berra. Payne must have labored over the details of that car, and the expressions on those faces, and making those figures interact, and creating the jaunty angle with the car hovering mid-bounce, yet all of these complex elements come together like a snap of the fingers.
The picture has a cohesion and liveliness that makes the hard work look easy.
To understand what distinguishes Payne's work, it might help to focus on a few details from this picture of a man floating away (a la Renee Magritte) :
At first it appears he is wearing a conventional gray flannel suit, but a closer look reveals that Payne used a purple(!) watercolor wash, with flowing striations deliberately left exposed:
A less confident artist would have painted the suit gray, and painstakingly drawn in the pin stripes.
Those trees and bushes in the background may look realistic but up close we see they are painted very free and abstract. Rather than make everything in the picture uniformly detailed, Payne understands how to prioritize a picture. He understands design:
As realistic as Payne's figures may sometimes seem, he frequently elongates and distorts them for the sake of the picture. Heads are stretched and extruded (see below) and ears are pulled out asymmetrically (see portrait of Vladmir Putin, above):
It takes a strong center of gravity to work like this. It's a far tougher job than merely capturing a likeness, and it's one of the reasons why Payne's work is so admired.