I remember Lego Creator, and still have it. I definitely enjoyed it when I played it, but Blockland is better in nearly every way. The series went straight downhill afterwards though, since they barely included any building, and they lagged horribly for me (mostly the Harry Potter ones). However, each had its own merits, some of which I wouldn't mind seeing implemented in Blockland (train track building, interesting building worlds with different sections, etc).
In Creator, did anyone else ever get the glitch where occasionally the bricks you place end up flying off to the edges of the map for no particular reason?