How do We/Sony Determine whether Move is a success or not?

[M.U.G.E.N]

first thing's first

does it work?

Success

does it have good feedback (media and others who tried it)?

Success

does it have the approval of the majority of PS3's current fanbase?

Success

Does it have a solid game line up that keeps on building as time goes by?

Success

Does it have good 3rd party support?

Success

Will it sell well? (doesn't have to be 20 million in 4 days success..just because Coca Cola is huge doesn't mean Pepsi is a failure for the company. People seem to miss this concept)

This answer will be provided with time...I would give it at least 1-2 years to show this

So yeah, so far so good.