- IMHO - their standard of proof is "would an average person be confused as to ownership of that name" just by you asking the question here - you already know the answer - with Google and Froogle - the average person would be confused, and therefore they would have a case.
Remember, even if you are right, and they don't want you playing in their sandbox, they have more lawyers than you do - so their strategy would be to make you get a lawyer and drain away your resources - never needing to prove a point at all. just be careful