One reason I haven't learned anything about IPv6 is because of how ugly the new format is. It's 128 bits divided into "48 bits for routing prefix, 16 bits for subnet id, and 64 bits for interface number." But the preferred encoding for such a thing is hex, meaning it winds up looking like 2001:0DB8:AC10:FE01:: (the interface number is omitted here, as is allowed by the protocol.) Compare that to an IPv4 address like "99.231.39.210" from the standpoint of visual appeal...
I don't have a point. Visual appeal isn't really a valid reason to dislike a design. Neither v6 nor v4 are "easy for humans." I'm pretty sure my illogical prejudice might be due to me growing up with IPv4 and never knowing anything else. Also IPv4 superficially resembles a phone number, which are quite comfortable for humans. So the fact that an IPv6 address contains so many more symbols than an IPv4 address is ... a little jarring. I know for a fact that I can instantly discern between IPv4 addresses (e.g. in log files or any other list) and tend to notice ones I've seen before based on their "shape" (like "8.8.193.39" has a totally different shape from "285.89.15.232") but IPv6 addresses are all visually uniform so it's much harder to recognize addresses you've seen before. This, again, doesn't really matter very much... What are the chances I'm going to be visually noticing oddities in lists of IP addresses? ... but it was kind of a nice feature.
Couldn't the first 64 bits of IPv6 addresses be encoded with a-z and 0-9, like domain names? Having a-z and 0-9 means there are 37 possibilities, and log(37^13)/log(2) is 68, meaning 13 a-z0-9 characters are sufficient to encode any 64-bit number. That way, IPv6 addresses would look like "d1mfx888qgnf3" or "fxyotvii435fb". That seems way less jarring of a transition than "2001:0DB8:AC10:FE01::" and it seems easier for people to remember 13 random [a-z0-9] chars than 16 random [A-F0-9] chars.
I mean, obviously this is all moot; the protocols probably won't ever change. I just wish some extra thought had been put into making IPv6 pleasant. I've only ever heard people complain about IPv6... no one seems to love it, which is generally a bad sign in a new design. On the other hand, the world will probably need IPv6 pretty soon, so maybe it doesn't matter whether it's pleasing. It would've helped its adoption rate, though.
Of course, the most obvious reason I've learned nothing about IPv6 is because IPv4 still works, and I have more important things to learn. Whenever IPv4 stops working, everyone will be forced to learn IPv6 regardless of how painful it is. I wonder when that will be?