Yesterday, Microsoft has started delivering updated Cortana experience to users. In the new update, users will be presented with stock updates and news updates on personalized topics. The information on watchlist and topics are used from the Bing Finance and Bing news apps. When you add a new stock to your watch list on Bing Finance app, Cortana will automatically use that. Similarly, if you follow news related any particular topic using Bing News app, Cortana will make use of that.
Also, I noticed few UI tweaks such as lines between different sections. Did you notice any other changes with this update?