There is 2 very important factors in this post for expansion..
1: New content, new max levels and areas.. all great..
2: More importantly for the game, the mention of COMING SOON..
When people know more new content is on the way, they stay interested and keep coming back. If the devs can hint at long term expansions and additions people stick round eagerly awaiting such events. The more active the player base, the more fun the game!
I am hopeing to see more 'COMING SOON' postings, not just a day before maintenance though 8]