... without any explanation as to "why"?  There's lots of legitimate reasons why a provider or client can cancel an appointment less than 24 hours before.  And sometimes people run late for good reasons, e.g. an accident on the highway snarls traffic.  

I do like the idea of being able to document NCNSes for both providers and hobbyists. But I think there needs to be some rules on it. For example, the date and time of the appointment must be stated when making the report (it would not be published however) and the report can be made no less than one week after the NCNS. That allows time for whoever did the NCNS to communicate with the other person and clear things up if possible.

One or more hours cancellation notice should suffice unless extraordinary rendezvous, session time or other arrangements were planned or expected.

NOT informing of running late is simply inexcusable in this age of cell phones, texting and internet. And I don't care if it's a "family emergency", major road closure or act of God it takes 10 seconds or less to dial one's cell phone if your still conscious and breathing

... blacklist website. there's enough of those around.  

bad idea all around.  

that's the Juicy Details are for in the review.

honestly i could care less what another lady tells me someone looks like. i hate the rating scale, we all have different ideas of what a ten is.
if i knew someone ncnsed i would not book them without partial payment upfront. especially if i was touring. there could be a "cancelled two hours prior, but sent cancelation fee." or for a lady, "she ran 20 mins late, but stayed a total of 80 minutes to make up for it."

that would be great!!

representative of a damn thing. Context matters, and would not be captured by a "metric". What might be indicative of performance is a rate of NCNS/date - great if you can get the info required for the denominator, meaningless without it.  

Just get over it.

I like the idea of being able to post the names of providers who do not show and do not call. It is inexcusable. I had a provider keep me waiting in a hotel parking lot for 1 hour after she texted me to confirm only 30 minutes before the appointment. I texted and wrote to her several times and she has yet to respond.

Too many explanations for the latter two.  Let's keep the focus on the most important problems, which is the No Shows.
Now if you made 1) cancellations within ONE HOUR, I might go along with that, because that is almost just as bad as a no show.