So far, this is the smoothest large scale MMO launch I've ever seen. No lag, no queues, and it's performing very well on my mid-range system.
Of course the real test will be how it scales as they move in the masses. But this staggered loading of players to keep the lowbie areas from getting overwhelmed seems like a very good idea. So was assigning guilds to servers. For the first week in RIFT I had to deal with 6 hour queues, not because there weren't enough servers, but because my guild randomly choose a server that turned out to have an ultra high population.