Tipa thinks that social platforms will kill the MMORPG. Syp thinks 2011 is the end of the WoW era. And quite a lot of other blogger interpreted the announcement of patch 4.3 as sign of World of Warcraft's imminent death. Which is curious, because the new features announced aren't actually all that special or stand out in any way compared to features introduced in previous patches. Sorry, an appearance tab, old armor storage, and a looking-for-raid functionality is pretty much par for the course, and way less change than for example the introduction of the Dungeon Finder was.
World of Warcraft is soon to be 7 years old. Any game gets boring after playing it for years and for thousands of hours. I'm bored of WoW. I'm bored of quest-based fantasy MMORPGs in general. But I know that this is something that happens in my head, and not some weird conspiracy that colluded to make all fantasy MMORPGs worse with every patch.
And yes, the games industry like many other entertainment industries has fashion cycles, where everybody appears to be running after the same holy grail for some time, only to give up on the chase and go after something completely different the next year. MMORPGs are not only out of fashion, they are already two generations out of fashions, with the social games that were supposed to kill them going out of fashion already. These days everybody is making lobby-based "always online" single-player and multi-player games, preferably with a Free2Play business model.
That doesn't mean that MMORPGs in general or WoW in particular are dead. Rift claims to be the number 2 MMORPG with 1 million "customers", carefully avoiding the term "subscribers". SWTOR has high hopes for attracting 3 million players. At the current rate of player loss, World of Warcraft will stop to be number 1 MMORPG in the year 2020. There is no reason whatsoever to believe that WoW won't still be around in 2020. And a bunch of other MMORPGs will also still be around. There will still be success stories, with some games like Guild Wars 2 looking quite promising, and people getting excited about the WildStar trailer.
The only thing that is dead is the MMORPG gold rush, and that is something to be thankful for. It only created a huge number of very bad games in the hope of getting rich quick. Surprise, surprise, video game players aren't total idiots, and bad games don't really do well. Especially not if you have a business model where you expect your customers to keep paying for a long time, instead of selling them a game they can't test first and running with the money before the customer finds out the game is bad. For all the possible objections one can have against the Free2Play model, it does force game developers to make games that are high quality, because otherwise the players never move past the free content.