Too soon after Christmas. The best thing is for an update in the fall, which would PISS me off and many other people, so they can sell through the Christmas season. If not, sell the current model through the Christmas season and wait til next summer.
How Apple handles the iPad refresh is going to be a delicate situation:
1) refresh this fall for the Christmas is too soon for early adopters
2) refresh right after Christmas makes all those Xmas gifts obsolete
Best time for refresh would be early summer or late spring.