Here's my view on what will happen...
A) Everyone will flock to Progression server and kill the current live servers (because EQ doesn't have enough compitition already from games like WoW and its own sister, EQ2)
OR
B) It will take a month for people to be level 70 and have all expansions unlocked and this will be the same as a new live server and all the novelty will wear off in less than 2 months, tops. When this is old and busted and all is said and done, nothing will have changed and people will STILL complain about something.
Maybe I'm wrong, who knows. Happened before.