Personally I think they should do the duty finder just like they are supposedly looking at doing transfers. After some time (6 months?) integrate them and make everything free for all but for the first 6 months I rather see them seperated. This is more for my own personal liking, not saying its the best choice at the macro level of the game. I just really enjoy the idea of starting fresh in a game and trying to lead the way; yes people will be able to go online and read walk thru's etc but I just don't like the idea of some high levels raising new classes and already either having a holier then though attitude or on the other end trying to help too much.
I think we will have plenty of options for grouping by keeping the legacy and non-legacy servers separate; let the new people try and retain the "new" feeling for as long as we can! Also can you trade in dungeons? If so isn't that a way to transfer shit from a legacy server to a new one? Anyways, not a big deal either way I just really enjoyed being one of the first in the community pushing through things and this kind of ruins it on a few levels but if they think it will help the overall population then so be it.