Blizzard Entertainment recently made the speculation of many a fan site a reality with the announcement of World of WarCraft: Cataclysm. The third expansion for WoW looks like it’s going to change the game in a fundamentally different way than The Burning Crusade and Wrath of the Lich King, the two expansions that precede Cataclysm.

The key difference is that TBC and WotLK, as expansions, primarily filled in blank spaces on the map of Azeroth. A few changes were made in old zones to facilitate the new content — the shifting of NPCs to Outland, or the construction of new travel hubs to reach Northrend — but for the most part, the areas from classic, or “vanilla”, WoW remained unchanged.

Cataclysm will break widely from this pattern. While content patches have had their effect on the existing areas of the game world (opening the gates of Ahn-Qiraj; the construction of the Argent Coliseum), and the “phasing” techniques introduced for WotLK were put to good use reshaping zones to reflect player actions, this new expansion will be dramatically altering old world content forever, and for everyone.

In brief, disastrous events are radically changing places players have grown familiar with. Some locations are flooded, others are overrun with lava, still others have sprung into new lushness and vitality. All this is being worked into the storyline of the Cataclysm expansion, with the added benefit of allowing the WoW developers to put everything they’ve learned designing new content to work in older, lower-level areas.

Indeed, for all the beauty of Northrend and strange majesty of Outland, many players experienced only a taste of Blizzard’s labor. The classic problem with the MMO system is that new content is produced to be tacked on after existing content — to appease those who have reached the end and wish there to be farther to go.

New races, as those in Burning Crusade, and now in Cataclysm, are one way to inject new material for everyone to enjoy. All players are able to create new characters in these new starting areas without needing to progress through existing content to see the new parts. Cataclysm is also allowing new race and class combinations, creating more opportunities for low-level newness.

Interestingly, Blizzard is also restructuring some old, lower-level content to be challenging to the current top end; in a short while the old Onyxia raid instance will be re-release with a version tuned for level 80 players. A similar retuning was announced for the instances of Dead Mines and Shadowfang Keep for Cataclysm.

The usefulness of this strategy is less immediately obvious than making new content that is available at low levels — why bother taking old content and shifting upward for the top-tier to enjoy? But the satisfaction of gamer nostalgia, not to mention the very real opportunity to make something new while avoiding creating it from scratch, make it a sound choice (even if the storyline explanations may end up a little contrived).

Revamping old content in this way is a likely crowd-pleaser, for veterans and newcomers (who may have missed such content the first time around) alike. How well the choice to drastically chance old zones completely will go over, however, is far from clear. Certainly some will be distressed to see favorite old content gone, or cry foul over lore developments for beloved zones and characters.

Cataclysm may be more of a gamble than WoW’s past expansions. Granted, the size of Blizzard’s playerbase means any expansion is almost bound for success, but I’m glad to see that the biggest player in the MMO arena isn’t resting on their laurels or sticking to business as usual. Count me as a fan — though if Garrosh Hellscream is indeed becoming the new Warchief of the Horde, I may have some difficult choices to make in the months ahead.