The article you linked is a horrible collection of Dilbertian platitudes from a PR guy, along the lines of "use synergy" and "work smarter not harder". Most points brought up are either "meh" obvious or not even true of WoW. The articles provides no insight into Blizzard's game design philosophy and amount to little more than "Yes, we're great, we know".

For real insight into the thought process behind WoW's design, look up Rob Pardo's keynote address at Austin Game Conference 2006.

As far as innovation, Blizzard does innovate, just not where it's immediately obvious. Blizzard does not innovate in core gameplay: they just take an establish gameplay model and try to improve it by emphasising the "fun" parts and pruning away the "boring" ones.

Blizzard is a leading innovator in user interfaces. They've been hard at work refining the control schemes of their games over the years, and most RTS and MMO games on the market are now copying what Blizzard came up with.

Blizzard is also an innovator in high-performance stylized graphics. The strong art direction and craftsmanship of WoW's graphics allow it to look good, age well, and run well on almost all computers.

Blizzard is an innovator in character design, with customizable skill trees for player characters and abilities that complement each other as well as abilities of other characters well.

Above all else, however, Blizzard is a craftsman company. Thier goal is always to create a product whose parts fit and work seemalessly together. Making the product truly original is secondary and even somewhat detrimental to that goal.
 

I agree with Mr. Gamer and his comments about reading Pardo's address from a few years ago for valid Blizzard design philosophy. I did read this article a few months ago and found it a bunch of typical corporate business mantra mumbo jumbo.

Here are a few of the points I really disagree with:

1. RELY ON CRITICS

Blizzard doesn't rely on critics at all, in fact they are infamous for ignoring them. When is the last time that Rob Pardo, Jeff Kaplan or Tom Chilton ever bothered to engage the WoW public on an independent forum either online or in person? I can't think of any.

Also, these guys never bother to post on game design forums or blogs. It's like they are purposely insulating themselves from the public and their fellow game designers.

3. MAKE CONTINUAL IMPROVEMENTS

This is untrue to a large extent. Unless it's PVP of course which has been a continual disaster of too much meddling and tinkering.

As far as other real improvements: where is guild housing that many have asked for for years now? Where are guild halls? Where is the ability to make a dynamic impact on the world? Where are the live quests and events?

Blizzard doesn't care about continual improvements as long as people keep subscribing. Expect the improvements to show up when people start leaving en masse.

5. DESIGN FOR DIFFERENT KINDS OF CUSTOMERS

Another load of hogwash. The recent Bartle controversy was about the paucity of features in WoW for socializers and explorers. Blizzard focuses entirely on achievers and killers and pays scant lip service to all other types of people who value other things such as role-playing.

Look elsewhere if you want serious information on Blizzard's design philosophy.
 

This list was torn down when it first came up. What can be taken away from the article is that Blizzard follows some of these "innovations" where as most companies just talk about them.
 

Nothing wins over the masses in our culture like success, you can then rewrite history as much as you like and the majority will agree.

I don't see innovation on this list, what I see is successful implementation.

Read the entire article again only think of the title "11 implementation lessons from the creators of World of Warcraft". Then it makes a lot more sense.