Reminds me of:
They looked different enough aestetically, so Sony could'nt sue for s***.
Likewise, Sony Motion+addon and Wiimote+addon look aestetically different enough, so Nintendo cant sue for s***.
When it comes to the technology itself(the innards) of the two competing motion controllers, they're completely different designs. Again. Nintendo cant sue for s***.
Nintendo knows this, Sony knows this, Nintendo's army(literally) of lawyers knows this and so does Sony's lawyers. (Altough im sure Nintendo management and employees are having a laugh)