DD8's school uses IXL and it appears more "drill oriented" from what I have seen. I have the overall impression that the school uses it as a reinforcement of what was learned in class. It does not appear to entertain the child in any way, but if your child enjoys feeling a sense of mastery they may enjoy this program. DD is assigned IXL as homework, so it has never been optional for her.

Dreambox has entertaining graphics and story lines that go along with the math - its format seems geared towards the younger set. They definitely try to instruct/explain concepts at times, rather than just asking the child questions. I do not think I would start Dreambox it with a child over age 8.