Theres lots of parts which are just wierd/ugly/inconsistent (like the water). Whilst the old map may please a few old players, it's not necessarily appealing to new players, which at the end of the day, is what we need. Theres also the problem that a lot of the old content its very basic/broken, and would need a lot of touching up. Scripting in particular would be very difficult because of all the changes since some of the was made (NPC Server, GS2).
You then have to add all the new content that's been released, and that just ends up changing what you have. I guess most of you can appreciate how different the overworld has looked each year because of all the changes.
Eventually you end up taking a HUGE ammount of time, when instead you can get very similar results by retouching up the best parts from the old overworld, and integrating them into the new one.
Just my 2 pennies.
I should probably add though, following discussion here, that if people really do want it, and there will be benefits to doing it, then I'm certainly not going to try and stop it.
