I preferred it when the two categories (preschool and daycare) were split because it was easier to find posts relative to your needs. Ages 0-2 and sometimes 0-3 are always in daycare not preschool. When the forum was just daycare, it was much easier to find relevant posts rather than read about a place and then find out again and again that it only services preschool age kids.
There was some cross over for ages 3+ in the preschool/daycare forums as most daycares do some type of preschool component. What was nice though was that the posts about centers which provide only full day/full week options where in daycare while the centers that provided a options less than full week/full day hybrid mix (full day, half day, part-week, full week, before or after care options) were in the preschool forum.