Crossworld visiting is the best thing they've implemented since ARR, there, I said it.
It makes it possible for players to buy goods on the MB for less than 1mil a pop, as someone who has played on Midgarsormr, Balmung for the past five years I can calmly tell you that this makes the less populated servers more playable, cause you won't have to do the hellish grind to get basic items on mb.
Will people make less money? probably, but overall this enables people on locked servers to play with their newbie friends who had to create a character on a non-locked server, and that's awesome.