Apple's next version of the Apple Watch will reportedly enter production in the third quarter of this year, for a debut alongside the iPhone 7. This comes from KGI's Ming-Chi Kuo, who also expects the next version of the smartwatch to retain the form factor of the current model.
In essence, 2016's Apple Watch 2 will see some under-the-hood spec improvements and possibly minor form factor changes, while fans will have to wait until 2017 for a massively redesigned wearable from Apple.
If this is accurate, this would put the Apple Watch on a similar "tick-tock" upgrade cycle that we've seen with the iPhone for years. It's been rumored that the next version of the watch will feature more functionality as an independent device, with decreased reliance on a connection to an iPhone.