And what of the keyboard? Since the Go is a completely different size than past models, Microsoft had to design an entirely new Type Cover. And, unfortunately, it's once again sold separately for $99. You could also step up to the more premium Alcantara version for $129 -- that's the same cloth-like material used on the Surface Laptop and the Surface Pro's keyboards.

Based on my brief time with it, the Surface Go's Type Cover feels just as comfortable as its larger siblings. And instead of being completely flat, every key is slightly curved in the middle, making it easier for your fingers to hit them. The trackpad, meanwhile, is surprisingly large, smooth to the touch and responsive. The Type Cover adds another 0.5 pounds to the Go's weight, but the combined system still feels light and easy to hold.

As you'd expect, the Go also supports Microsoft's $90 Surface Pen, which is also sold separately. Additionally, there's the new $35 Surface Mobile Mouse, a cheaper alternative to the $80 Surface Arc Mouse. It's comfortable to use, but you can tell it's an inexpensive mouse, thanks to its plastic case.

While the Go isn't the dual-screen, pocket-sized Surface I've been longing for (though Microsoft is rumored to be working on that), it's an intriguing step forward for Microsoft. It's a tiny machine that'll let you do just about everything you could with your normal Windows PCs, save for playing games. And while Apple is focused on similar portable productivity with the more expensive iPad Pro, it's paying less attention to the standard iPad. That leaves the door open for Microsoft to truly innovate with a $500 system (including the Surface Go and its keyboard). I wouldn't be surprised to see Microsoft take this case, throw in a Snapdragon processor with integrated LTE, and finally deliver a killer Always Connected PC.

The Surface Go is available to pre-order today in the US, Canada and other markets. You can expect to see it in stores on August 2nd.