1) As an editor it’s novel for his high performance across so many platforms.
2) As a plug-in platform with a simple marketplace it’s the first time I’ve seen this work well across many types of dev groups. “Easy enough” for html designers, and data scientists as well as traditional programmers. Plug-ins exist for other tools, but not as easily put together as this.
3) The release schedule is so rapid. At least monthly releases with new features with lots of community ideas realized.
4) Within Microsoft’s culture it turns the decades old visual studio model (good performance but locked into Windows and costly) on its head. So this is really new for Microsoft. (Even though I think it would be innovative from any company, but there aren’t any other companies I know that make money from developers so don’t actually need to charge for dev tools).