Iterate in the wild
Jason Fried on the Big Web Show episode 106:
The best testing I've ever seen is shipping something to real people who use it every single day, and depend on it. And, charging people for it. They are the ones that give you feedback.
I hear this all the time from other people: How do you get your customers to tell you what they think? I say: You charge them for your product! Because when people pay for something they tell you what they think.
The best way to get feedback is to ship something, charge for it, and then iterate in the wild; and, make it better over time. That is how everything becomes great.
Things don't become great in the lab.
You just cannot validate a new product by asking people if they will like it. Not until they use and pay for the product will you know if they liked it.