According to AppleInsider, Apple is planning to launch two different iterations of Apple Watch 2 by the end of this year. One of the versions will come with a better processor, while the other version will boast a GPS Radio along with a barometer for better geo-location capabilities. The second iteration is also said to have more battery life and some additional features.
As far as designs are concerned, they will stay the same. If you have been using the current version of Apple Watch, then you will have no trouble adjusting to the new ones.
Looking at the aforementioned details, it is pretty safe to assume that the second version with more features will cost a whole lot more as well. So, if you are looking to get Apple Watch 2, you better start saving now.