According to the website's source, who remained anonymous due to their "involvement at Apple", the company would offer an engraving option similar to that of products like the iPhone, iPad, and iPod lines.
The contact, however, remains unsure of whether the feature would be available on the Apple Watch's launch date or not. They remain "almost certain", however, that the customization option will emerge for the device eventually.
An engraving option certainly makes sense for Apple's new fashion-focused wearable, especially considering that essentially all of the company's mobile products include the personalization option, but the small footprint of the Watch does raise questions on where the actual engraving would be located.
The heart rate sensor located on the device's backside takes up nearly all of the real estate of the 38mm or 42 mm device, although drastic character count limitations could perhaps fit truncated messages around the sensor. There's also a possibility that more room could be found on the device's side opposite the Digital Crown, but until Apple officially announces the engraving service, it remains to be seen where the personal messages would fit onto the wearable.
Despite being announced nearly six months ago, a number of details on the Apple Watch have yet to be revealed in the lead-up to its April launch. Last week, the company sent out invites for the "Spring Forward" media event to take place Monday, March 9 and for which most evidence points towards a heavy focus on pricing and launch day details for the new wearable device.