Yes. The license key you receive will work on either platform.
If you switch from one platform to the other (or if you have a Mac at home and PC at work, or vice versa), you can install the software on the new computer and use the same license key.
If you switch from one platform to the other (or if you have a Mac at home and PC at work, or vice versa), you can install the software on the new computer and use the same license key.