Most of my original complaints about GoDaddy DNS were on the old ProxyObsession blog, so you may have missed it. What it came down to was I couldn't resolve my own domain name from home, but I could resolve it from anywhere else. GoDaddy finally fixed it but then that whole DMCA nastiness hit the fan and I was outtathere for good. Never looked back.
So... check it out...
What seems more likely is that the new owners of GoDaddy are trying to improve on the "Premium DNS" service, which appears to have been a failure. The Premium DNS service started around January, 2011. However, it appears not to be meeting their sales goals (99% of domains using GoDaddy DNS hosting are still using the free service)... We now know that GoDaddy is willing to block DNS queries. Will it continue, or will others follow? What will happen to the Internet if all DNS hosting companies follow the same path? Only time will tell.
That explains a lot.