I think this feature is long overdue and might actually help keeping certain realms from a total collapse, while adding a lot of convenience to others.
I'm looking at my experiences with EU Magtheridon, where a FCM offer had me impulsively move all my 70's to a realm that has such a messed up faction ratio that I found myself very much unable to group for just about anything once I hit 80 with my toons. Despite volunteering to tank with my druid, it was completely normal to spend like 90 minutes in LFG to do a heroic. Not at 3 am in the morning, but during prime time from 6-9 in the evening. Even though I had spent like 3-4 hours each day trying to get something done, I had only 20-something emblems to show after TWO WEEKS.
So far I've paid for 3 characters to move back to where they came from because of the grouping problems, and I think it might have been avoidable if that new feature had been in place already.