As well as what all the girls above have mentioned try hanging around a little longer as you fill out forms etc or pretend to read notice boards and listen to how the staff speak to the children and to each other. I've worked in child care for 5 years and in that time staff came and went... sometimes morale would drop and often it would be the children who would suffer as frustrated staff members would sometimes take it out on the children. Good staff don't speak "down" to children or poorly to each other... and if you have good staff you have a good centre... doesn't matter how nice the facilities are or the impressive programs... the things children notice most and are affected by the most is the prevailing atmosphere... if you have that everything else will fall into place.

Good luck!