Wow, this is a really cool idea! I'd add some stuff about the API interface to the screencast. To me, that's the most interesting part.
FYI, I get a server error when I try the Run Utility example at http://www.utilitymill.com/help/api
FYI, I get a server error when I try the Run Utility example at http://www.utilitymill.com/help/api
I'll have to make some more screencasts when I get a chance, including the API.
BTW, I fixed the API error you were having. Sorry about that.
Sounds pretty similar to Yahoo Pipes. On the other hand, this site actually works.