In the new Cataclysm zones in WOW there is an entirely different style of play while doing quests. In the old game quests were largely optional - you could do them or not and nothing changed and if you ignored some of them it really didn't matter. In the new model things are completely different because quests are telling a gigantic story with your character at the heart of it and you cannot avoid nor skip them. To complete each of the zones in question and see the final quest you have to do absolutely everything in the zone first. Because of the new phasing technology employed everywhere you also have to do everything in precisely the order the quest designers set up. The number of options available to the player is thus very small in terms of what comes next. That is offset by the fact that quests are now vastly better. There are all kinds of boss fights you can do solo, the world actively changes to reflect the things you as a player have accomplished and the things you do feel much more epic because you can see the effects of your efforts. The new style is much better for those who want to experience a story or watch a movie or feel epic but much worse for those who want freedom to explore and do their own thing.
There are many complaints about WOW but two big ones over the years are that:
1. Quests the players do have no impact on the world and nothing changes no matter what supposedly has been done.
2. WOW is too much of a theme park where the player is forced onto the straight and narrow instead of simply going out there to see what can be seen.
Clearly Blizzard decided that the first complaint was one they should address - and they did! The question is whether they went too far, and I think they did, but only a little. The trouble with this new model is 100% of the quests are mandatory so having bizarre, challenging or strange mechanics either have to be made trivial or they end up annoying a lot of people. In particular the jousting quest in Hyjal would have been a good place to have a little side quest - you could do the jousting or continue with the main questline. I would enjoy it greatly if the main plot series was designed in the current fashion but there were side quests, things that weren't entirely necessary to advance the plot, scattered around. While I don't like to give him too much credit, Gevlon actually had a neat idea to have the main questline for a zone have red ! and ? markers so players know that these are the really important quests to do and have optional ones be the normal gold colour. Everyone recognizes that you can't tell the epic story without a strict chain of quests but giving players the option to complete a few extra things at the current hub or move on to bigger and better stuff would be nice.
All in all I really did like questing through the new zones and the phasing, new and better quest/bossfight mechanics and epic storytelling were a lot of fun. I do wish though that I could push ahead with the story and leave a few of the 'go find me 6 bottles of rum' quests for later. A happy medium between the old way and the new way looks to be the best way from where I sit.