Drag and drop has been around for years, heck Unity3D has been out for a long time, it was Mac only but was capable of deploying to Windows. I think that boost its popularity by a lot when releasing the Indie version for free.
Heck, I got into game creation through a Drag and Drop software, Klik N Play, I moved onto The Games Factory afterwards and the Clickteam software was really capable for making powerful 2D games without programming knowledge. But I saw Dark Basic and was like, "wow! I wanna learn to program!"
Torque has been around for quite a while too, whilst you can customise Torque's engine inside of C++ as you get access to the full source code, but it is basically drag & drop + scripting.
These tools certainly make developing games easier, however, they're not necessarily the top choice for game developers as you get less control and not everybody likes that and sometimes to get exactly what you want the best method is to build your own engine from the ground up. Probably why we haven't seen everybody jump to using already existing game engines (although people still build on top of them to make it more than just 'scripting' and using a drag and drop editor) and it's also probably why it's unlikely these tools will replace developers programming their own stuffs.
