With its boxier 3:2 display aspect ratio, the Surface Book comes out to 6 percent taller than the 13-inch Retina MacBook Pro, but slightly narrower.
If you get one of the higher-end Surface Books with discrete GPU (tucked away inside its keyboard), weights are about even. The lower-end Surface Books, with integrated graphics, are 4 percent lighter.
Like every other Surface, the Surface Book has a magnesium construction.
No color options for either device; it's silver all around.
Microsoft is downplaying the Surface Book as a tablet by calling it "clipboard mode," but you can remove the Surface Book's screen to use as a humongous slate.
This should be a big upgrade over the Surface Pro 3, as both the Surface Book and Surface Pro 4 have big glass trackpads – a lot like Apple's MacBooks.
Force Touch trackpad
The MacBook's touchpad, though, uses Apple's Force Touch tech, so clicking is no easier at the bottom than it is at the top.
The Surface Book's display is, based on area, about 6 percent bigger.
The Surface Book's pixel density is 18 percent sharper, but we've never once thought the Retina MacBook Pro's screen was remotely lacking in crispness.
The Surface Book's higher PPI could come in handy, though, when you use it as a giganto-tablet, where it will probably sit a little closer to your eyes.
Apple has yet to make (or show the slightest sign that it has any interest in making) a MacBook with a touch-sensitive display. The iPad Pro is the closest you'll likely get to that anytime soon.
Though the iPad Pro will use a stylus ("Pencil"), the Retina MacBook Pro doesn't support any kind of pen or stylus input.
Like the Surface Pro series, the Surface Book includes a Surface Pen in the box.
Both machines let you choose between Intel Core i5 and i7 processors, though the Surface's are newer 6th-generation Skylake CPUs (this early 2015 MacBook uses 5th-gen Broadwell processors).
Apple only offers integrated Intel graphics in this 13-inch model of the Retina MacBook Pro, but the more expensive Surface Book models have discrete Nvidia GeForce graphics – we just don't know the exact card yet.
Since those models have their discrete graphics cards stashed in their keyboards, you'll lose that extra GPU punch when using the Surface Book as a tablet.
RAM options are the same, though the 16 GB version is a made-to-order configuration for the MacBook (you won't find it in retail stores).
We don't know the specs of the Surface Book's battery, but both Microsoft and Apple are using the same estimate for video-watching.
Both machines start with 128 GB SSDs; if you like to store things like years worth of photos or videos, high-end games or virtual machines on your main drive, then you may need to pay for one of the more expensive models.
SD card slot
The Surface Book and Retina MacBook Pro each have a full-sized SD card slot – great for anyone who uses a non-wireless DSLR (and for discrete storage, at least on the MacBook).
Each laptop has two USB 3.0 ports.
If you want to hook up an external monitor so you can use your laptop as a desktop PC, then these are the ports to use (note that Thunderbolt is backwards compatible with Mini DisplayPort).
Though Microsoft is framing the Surface Book as a laptop, it has a tablet-like rear camera.
Facial recognition login
The Surface Book's front-facing camera lets you securely log into your machine using your face instead of a password.
The Surface Book officially launches on October 26.
The 13-inch Retina MBP starts at US$200 cheaper than the Surface Book – and both of those entry-level models give you the same 128 GB internal storage. That extra money gets you a combination of Skylake processors, a slightly bigger and sharper (and touch-friendly) screen, and that bundled Surface Pen.
Stay tuned for Gizmag's Surface Book review. For more on Apple's laptop you can revisit our 2015 Retina MacBook Pro review.