I've been using it a little to automate really stupid simple programming tasks. I've found it's really bad at producing feasible code for anything beyond the grasp of a first-year CS student, but there's an awful lot of dumb code that needs to be written and it's certainly easier than doing it by hand.
As long as you're very precise about what you want, you don't expect too much, and you check its work, it's a pretty useful tool.