Blizzard have said that adding new zones in Azeroth would be cool, but also time consuming...

We would like to revisit and implement new content for Kalimdor and Eastern Kingdoms, but we have no estimate on updating all of the zones that people have talked about or if this will happen at all.

We always have to consider development time versus what is the most fun and currently we feel it will be more exciting to create new continents like Outland and Northrend, but we never know exactlywhat the future holds.

So you want to fly your mount in Azeroth? Contrary to what Blizzard intended, it is actually possible, but you will need to be a level 70 hunter funnily enough.

1. Level a hunter to 70
2. Put 1-2 talent points into Animal Handler (BM talent that increases pet %hit/mount speed)
3. Go through an instance portal, and you'll still be mounted. This works for flying mounts so I'm assuming it works just as well for regular ones too.