Who defines Value in the agile process?

I was a bit freaked last week by whether or not the work we are going to be releasing in a couple of iterations was providing the right value to the business. In the agile method I started to wonder who decides the value? As the Scrum Master and Partial Business Owner I had been doing this to a large extent - and as far as I have read this is normal and correct in most cases:

Roman Pilcher
What makes a good Product Owner

The other aspects of the role I feel I have been doing too, in particular, understanding the role of the customer. We've invested lots of time testing and asking our audience what they want. So, on the whole I feel this all feels ok.

So, why the freak? Well, I guess its because I wasn't sure that what the Product Owner and the wider business define as value was aligned. And I don't mean this as any intentional thing, I am just finding, when working with in agile, that building a business consensus on Value is a challenge.

So, what's the solution? Well, first thing is to spend more time with the stakeholders! We have a meeting in the diary which will hopefully resolve things. Will be interesting to see what happens.