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I get that error when I run web service calls between domains without first enabling Cross-Origin Resource Sharing (CORS). Add the following line somewhere near the top of your code. It should work for the life of the page.

$.support.cors = true;

With CORS enabled, I'm able to run web service calls between domains and even between different versions of SharePoint (2007 & 2010), either direction.
Also, you're referencing jQuery 1.11. I'm not sure how extensively Marc has tested that. You may want to switch to jQuery 1.10 for now.

Geoff