The actual text of the ToU says
You will not, and will not permit your users or other third parties to:
...
(c) modify, filter, obscure, or replace the text, images, or other content of Live Search results, including by changing the order in which Live Search results appear (but this limitation will not apply to Live Search results of type "Web"), intermixing Live Search results with search results from other sources, or intermixing with Live Search results any other content so that the other content appears to be part of Live Search results;
This means that:
1) you can reorder and interleave results with sourcetype = web (not the others, like image or video)
2) if you want to interleave, you need to mark clearly the data that comes from a different source than Live Search so that there is no confusion (e.g. a different style).
HTH
--Alessandro
