@Punyelf: Sorry, I was not feeling well and fell asleep while trying to stay up to date last night.
@All: It seems many posters have things entirely or partially backwards. Blizzard needs realms of suitable size ( = not too big) to connect with smaller ones. Just smashing the tiniest ones together is far less optimal solution. This approach was actually one of the faults of the original program. Tiny / small realms (in terms of ACTIVITY) should have been connected to big ones. Tarren Mill / Dentarg model should have been applied at a far wider scale back then.
This in turn leads to a situation, where Blizzard can not just disregard numerous suitably sized realms (in activity levels) when creating connections. Several of you are looking at things from wrong end, so to speak. There are very limited numbers of suitable “bigger” partners for connections and some of these “bigger” partners are far less active than others. More on this directly below.
On the topic of size… Just because something reads “High” or “Full” does NOT mean that it is currently very high ACTIVITY realm. Also, if you have 23 different “High” realms, just looking at the ingame list does NOT tell US, which of them have highest ACTIVITY numbers. That is the sort of knowledge we players do not see. Neither can we discern by just looking at the ingame list, which of the 23 has most horde / alliance. This is the sort of thing Punyelf meant. We have information, but it is not absolutely accurate, rather indicative and in some relation to the other realms.
If you have been paying attention, realms like Draenor and Silvermoon under normal circumstances read “Full”… and this is true, whether they currently have 237, 944, 3871 or 5324 players online. They both have (from my recollection from the time RealmPop still was available) in excess of 600 000 characters. That does not mean they both have over 100 000 active players, not even quite 100 000 active characters according to the data on WRP.
Pure number of characters does NOT tell us how ACTIVE a certain realm is. In addition, as some posters correctly noted, the ingame display is partially activity sensitive. In other words, if for example say two very similarly sized “Medium” realms have highly different current activity levels, one might appear “Medium”, while the other is temporarily showing “High”.
I will try compress the above as follows. Punyelf is NOT saying Blizzard is lying, but rather that the data WE see is not of absolutely exact nature. I hope I managed to make myself sufficiently clear. I also understand why some of you are confused. I have spent time reading the US threads as well and some people there also struggle with comprehending some connection decisions. It is quite clear that for some realms activity level does not reach numbers the population statistics might suggest.
A small footnote on the English language. It has NOT always been the common one. Enough time backward and clergy studied Latin, the nobility French in many countries… and for example the postal services still carry expressions such as “Par Avion” for air mail and “poste restante” is not English either… and some of you might also have heard the term “Lingua Franca”…
EDIT: Added a missing word.