The proper way for them to have done it, is for you to opt-in to sharing your music, as oppose to sneakily telling your facebook friends what you're listening to.
I'm at a start-up that is a follower of the lean startup movement, a term coined by Eric Ries.
The ideology behind a lean startup is a customer-centric approach where you build a minimum viable product (MVP) and always be learning from your customers and make changes till you build out something that they actually want to use. Be flexible on your vision, and don't waste time and resources to build out an amazing product that no one wants.
For a SaaS partner, conventions and meet ups are probably the best places to start. It helps when you're building a relationship by getting out of the office and talking to your customers, and cold calling isn't the warmest approach (duh). Meet-ups are a great opportunity to build relationships and get to know your customer's needs and eventually make the sell. As you keep talking to people, keep making notes of iterations on your product to build something that those customers want.
There are so many companies that have flopped in the past, such as WebVan, who built out expensive supply chains before really understanding their customer's needs. They were an early pioneer of e-commerce, but many argue that it grew too fast for people to really jump on board. Had they slowed down and spent time understanding their customer's needs, they wouldn't have over-invested in infrastructure.
In short, don't build out a product with all the features and functionality you want before you figure out what your customers want/need. As you talk to people about your MVP, you'll organically figure out who your pilot customers will be.
Get out of the office and talk to customers!
Suggested reading:
The Lean Startup by Eric Ries (fresh off the press!)
Running Lean by Ash Maurya http://www.runningleanhq.com/
Well stock exchanges offer tangible value for people who participate. The value of virtual good is limited and is basically a consumption good. Adding gambling to social games allow users to extract value from their favorite games.