I have been musing over the concept of travel in MMORPGs. I have two competing desires in any game I play. I want to be able to meet with friends and get anywhere I need at anytime, but I also want to have my character be able to live outside a town for a long time while being self sustainable and living off the land.
In my mind's eye, the fantasy setting almost demands that the adventuring character be able to walk out of a town and subsist for weeks on end without seeing a vendor or blacksmith. Creating your own arrows, making your own food, all take on a new importance when a town is not just a click away. Are you really a seasoned adventurer if you can just fly to town and sleep in a real bed and buy all your provisions? Imagine a world where striking out to rescue someone means stepping out into a world without a safety net. You can't just stop half-way there, fly to town, buy some more arrows, then fly back out. But, then, if you can fly, why wouldn't you just fly over the area and look for the missing individual.
But, like oil and water, these two ideas will probably never cross paths. Who wants to play a game where it takes days to cross an expanse? Especially when you want to play with your friend on the other side of the world today and not next Friday. Access is important to people, and limiting access is bad. Even when it destroys the sense of being in the wild and being a grizzled adventurer.