Yes but creating each individual part, and skinning the bones, is no different than doing the same in some tweening program, then importing the animation. Your still going to have to set up what you want to happen before you get any results. The bones system just keeps you from having to use expensive software.
There's really only two differences between the two. Using an animation package you can adjust each individual image from within the software, then using the bones you can make adjustments to the motions from within the software.
In the update, it's introduced as a "new bone movement behavior," keyword being behavior. As in, something that can be controlled and manipulated in real time.
Now, if this were just a feature included into Construct's picture editor, then yes, there would be no different than importing an animation from some animation package like Anime Studio.
But this isn't precanned animation. These are bones controlled via a behavior which can be manipulated in real time. With this, I imagine being able to create 2D ragdoll physics in Construct and even procedural animation, or even just less static, smoother looking animation in general than what using a precanned sprite animation allows.