Answering the question whether there is a likelihood of confusion between trademarks is not a easy question. Several elements have to be assessed and as these elements also influence each other and the circumstances of the case play a role, you sometimes just rely on your trademark instinct.
In case of a trademark infringement between band names, the music style of the bands could also play role. Really? Yes, according to the judge in Tennessee there is no likelihood of confusion between the (rather similar) band names Newboys and New Boyz as the former is a “Christian-music band” and the latter is connected with “sexually-charged hip-hop music”. Remarkable decision!
Source: Seattle Trademark Lawyer