We use it within the Accelerator (a collection of startup products). We use it as an alternative to WebEx and other conferencing tools when we can. It solves our need for dependable voice, video and screen sharing during remote calls.
I don't know that it has a dramatic advantage over competitors in price, but the quality is all around better than alternatives. So in that respect it has had a significant impact - less wasted time, better meetings.
I have used quite a range of these tools over time. Some work pretty well if all parties are using a laptop with high bandwidth. However, Zoom works extremely well when people are on different devices / media (like some on phone, some on computer). Others services either can't handle mixed device type calls at all, OR the quality suffers. The most common problem is a lag is introduced when you have a combination of computer and plain phone callers. This does not appear to be the case with Zoom.