Alright, lemme just construct a fort real quick for..... no particular reason :

Alright, so, Steam and the Whiterun Wolfhound were great ideas and perhaps the best thing ZOS could have done, and here is why.

ESO going to Steam has brought a wave of new players into ESO, and this can be seen in the starting towns, leveling zones, and generally most places in game. What this means is there will be more people in ESO to socialize with, quest with, interact with, PvP/PvE with, and just basically do all sorts of MMO things with.

This can be noted by, like I said, looking at new towns, but also looking to Cyrodiil. Now, before Steam and what not, if it was say 7:00 PM EST and you went to PvP, usually the most active server would really only be Wabbajack. Now, looking at the PvP campaign list, both Wabbajack and Dawnbreaker are more or less full, and when I tried to queue for Wabbajack I had a queue of about 60. So, more people = yay.

Now, for the thing no one wants to talk about, or the thing that people want to argue about... the wolfhound.

What the wolfhound did in this situation was it brought people even closer to wanting to play ESO since no one can deny that exclusive stuff is awesome. So, it increased ZOS's money gain even more, since not only are people buying the standard copy, as we see above with the population increase, but people are also spending more money for the Imperial Edition for all the perks and a dog. So yay, more people, more money to ZOS, ESO is less of a ghost town, wonderful!

BUT WAIT, THERE'S MORE!

What does more money to ZOS mean? "Oh yea, ZOS just wants more money because greedy blah blah" -_-... NO, thats not at all what that means! What that does mean, however, is that ZOS is funded. Now, lets look at Quakecon real quick. They dropped TONS of sweet juicy... omg I just want to roll around in it info about upcoming features for ESO. Now, stuff like that costs money... lots of money. So, without money, we get no features, no updates, nothing. Since ZOS is getting money from Steam, subscription payments, the whiterun wolfhound, and all that other wonderful stuff, they now have the money to fuel and develop those amazing new features and shiny new stuff we want.
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TL:DR because who needs reading, amiright?

ESO now has many more subscribers, is more active, more people to do stuff with.

Cyrodiil is more active, proof of the above.

Wolfhound gave more incentive for people to buy the game and play it, and lead to the above two.

Because of the above 3, ZOS is now funded and has money, which means they have money to spend on new features (stuff the revealed at Quakecon).

*hides in fortress*