Do they still roam the park or do you actually have to queue up at special times and places to meet the characters?
You will see them wandering round but that's usually because they're on their way to a proper M&G spot and they'll give you a wave but usually won't stop for photos/autos. The princesses even have hooded cloaks to hide them as they're going to and from the pavilion to avoid them getting mobbed!
The vast majority of character meets now are orgainsed queues at particular places because this stopped the rude free for all it was in the past.