Great right?! So I can explain a little bit if you're interested. Custom JSON ops are essentially a way of storing code on the blockchain so that developers can make apps more decentralized and transparent but at very low cost (free even). This enables something we refer to as "Soft Consensus" which I like to describe as "trust through validation" rather than "trust through decentralized computation." The idea behind protocols like EOS and Ethereum is that in order for users to trust apps, the computations powering those apps must be performed by the blockchain itself. Steem's approach is different. We say that, yes, there are SOME computations users want done by the blockchain like those relating to token transfers, token vests, voting actions, the storing of speech (i.e. content), and a few others. But that's it. Developers can't ask Steem to "calculate Pi to 1,000,000 decimal points."

Bounding the amount of computational work Steem can be asked to do enables the efficiency which allows for many of the special features of Steem like free transactions. This creates a unique opportunity for developers, in that they can decentralize the mechanics of their app without incurring the costs that come from having that code processed by the blockchain. Granted, this is something that you can do on practically any blockchain. The problem is that this would be extremely expensive to do with any other blockchain, therefore if you were going to store your code on Ethereum you might as well have it computed by Ethereum as well.

Soft Consensus only really makes sense on Steem because of the speed and fee-less nature of it. By hosting the code to your app on Steem you accomplish two things: 1. you enable your code to be audited by developers who can then validate that you are executing the on-chain code faithfully, and 2. you open your code to 3rd party developers. For example, because the market for SteemMonster exists in Soft Consensus, as far as Steem is concerned, there is no such thing as SteemMonsters, just a bunch of meaningless custom JSON ops. But inside those custom JSON ops is all the code powering their market, which 3rd parties can use to build their own apps. So now anyone can build their own market for SteemMonsters cards, which is how PeakMonsters.com exists.

It is my thesis that of all the code needed to power a given app, 99% of that code does not need to be decentralized at all. Of the code that need to be decentralized (i.e. on a blockchain), 99% of that code (the 1%) only needs to be in soft consensus where it can be audited. Only the remainder (1% of 1%) needs to be on-chain and executed on-chain. I believe that what we try to do with Steem is to look at that .01% of code that is super critical for decentralized applications, and add those to Steem. This enables Steem to perform those Smart Contracts exceptionally well, at an unrivaled low cost.

Hope that helps!