Very good article and overview explanation. However I would not recommend buying names with bitcoin, ripple, etc in them. Not only will it be oversaturated those names are brands and can / will be trademarked and you can still be hit with a UDRP. Only register generic names like,,, etc. There are tons of opportunities and no need to infringe on a brand name.

As mentioned earlier, knowing the potential value of a domain name is an invaluable skill. By adhering to basic guidelines such as those I listed above and through some of your own research, you’ll be able to pick names that offer you a higher chance of flipping them more easily. Remember, a net profit of $100 is still a profit, you must start somewhere.

Yandex replaced TCI with SQI (Site Quality Index). SQI looks similar to TCI, so I re-used the old TCI field, however all values are now the new SQI. Not all domains are checked yet, but all that had TCI > 0, are now switched to SQI and all newly added domains are also checked for SQI (starting today). Updating all domains will take a couple months.

Yes, we port in all of the domains from NameJet, SnapNames, etc. There are a lot of great deals to be found. Some are absolute trash of course but if you can sift through them and put some time in (hopefully that is what we are trying to do with our tools is save time and give some value add with the SEO metrics, alerts, etc.) then you can find some great bargains.
Just like a property listing, except much simpler, domain marketplaces are basically massive lists of domain names that are up for sale. The process of using them is simple. Buy a domain and park it, then list your domain on the marketplace for a price you’re willing to let it go for. Once the domain is sold, the marketplace takes a cut and then passes on the remaining funds to you.
Domain names expire when someone decides to stop renewing it. They may not be available to register immediately. We update the search index every night, so some names may already be renewed or re-registered. Some may become available in a few days. Some registrars, like GoDaddy, will let you buy a name that one of their own customers expire immediately. When you find a name you like, just click on it to try backordering the name!
Justifiably, any attribute or factor that is known to be influencing prices, is doing so as it leads to demand. On how easy basis of such factor demand is raised and thus the price. Hence, these domains of media like segments as you say like gain worth from the same factors that lead to demand. When price is enhanced or goes premium, the domains are thus known as premium domains.
Here's an old post on search engine roundtable that claims google's policy is to discount previous backlink juice when a domain changes ownership.  I'm not convinced whether this is actually true or something Google says to discourage excessive domain buying / 301 redirecting for SEO benefit.  The comments above seem to give varying opinions on this matter. Would be great to get to the bottom of that one!
Many non-savvy internet users may not even be aware of the existence of other extensions. That said, because there are many new extensions popping up every now and then, you can often find amazing one word and 3-letter domain names with these new extensions that are otherwise almost impossible to find unregistered in the .com world. Additionally, these new extensions are becoming more and more familiar to users every day, hence it's almost certain that their value will continue to increase as time passes and wider adoption manifests.