The Surface design has aged quite well, so the company didn't need to make any major changes. It could have done smaller things like adding a Thunderbolt 3 port, moving the headphone jack lower on the clipboard part, or adding a fingerprint reader for situations where the Windows Hello camera is not ideal to authenticate, but that didn't happen with the Surface Book 3.
The internals now include 10th generation (Ice Lake), quad-core Intel processors paired with up to 32 GB of RAM. You also get the option to have either a GeForce GTX 1650, 1660 Ti Max-Q or a Quadro RTX 3000 Max-Q GPU depending on what you want to do with your Surface Book 3.
Microsoft says that using CAD design tools like Solidworks with the Quadro-based version can reduce render time by about 50 percent.
With all that processing power, one of the issues with the previous 15-inch Surface Book was that the charger wouldn't provide enough juice, so the battery would also discharge slowly when doing intensive stuff like gaming or anything that approached a full load. Microsoft says the new charger is able to provide 127 W, to ensure it has a bit of extra power to charge the battery as well.
The new SSD inside the Surface Book 3 is significantly faster than the previous generation, and Microsoft claims that you can expect around 15.5 hours of battery life on the 13-inch variant and 17.5 hours on the 15-inch, depending on your workload.
The port selection remains the same: two USB-A ports, a Surface Connect port, a full size card reader, and a single USB-C port with USB Power Delivery 3.0 capabilities but no Thunderbolt 3. Apparently that's because Microsoft thinks it would be a security issue, since anyone with a well-prepared USB drive would be able to exploit the direct memory access nature of a Thunderbolt port. This means there's no support for external GPUs -- not now nor in the foreseeable future.
Microsoft also announced the Surface Dock 2 priced at $259.99 that sports a longer cable, fast charging, and four USB-C ports with support for up to two 4K monitors at 60 Hz. And since you're gonna want to use wireless headphones with the new Surface Book, the company introduced the Surface Earbuds and an updated version of the Surface Headphones, at $199 and $249, respectively. Both offer touch gesture support for controlling calls and audio playback.
Whether or not you should buy the Surface Book 3 depends on how much you need a detachable tablet, pen support, and whether you can live with the limitation of having 15 W CPUs in a device with a starting price of $1,599. Microsoft will start shipping the new Surface Book on May 21 in the US and Canada.