[yakisoft]

I'm struggling to see how Twitter is of any use in finding customers.

On the other hand spending on Adwords links me directly to people who are looking for my products. For me it is consistent, reliable, directly measurable and profitable.

[avk]

I've had luck converting people tweeting about the problem my product solves to beta users. I'm sure it depends on who your customers are and how likely they are to express themselves on Twitter and other social media.