A more elaborate answer...
I can't say I can speak to CPA (on Facebook, at least) but I believe any marketing campaign on a social networking site can be successful if you stick to it. You have to remember that many of these communities are "self-contained" so you have to do a lot of networking and promotion natively to get real results. NoFollow pages can prevent people from finding you on a specific platform or community so it's tricky business.
I just did a Google search for known Facebook pages and only got top-level Facebook hits. That should give you an idea of what you're dealing with. Basically, you have to cultivate a unique community within Facebook and hope that you can drive some of your audience and key influencers to other, more organic (and
interoperable) platforms. You'll have to be very active and connected on Facebook to reap the benefits.
I'd recommend using FBConnect and other syndication/sharing tools to keep updates on Facebook frequent. Having Twitter updates appear on Facebook is also helpful. Most importantly, be sure to reach out to those that support you on Facebook. Respond to comments in a timely manner to show your appreciation. Once you develop some loyal "friends", you'll get enough hits to attain the conversion rates to make CPA worthwhile.
Here's a good article for more on
Cost-Per-Action (CPA) network marketing:
Cpa Network Marketing - How Does It Really Work?
Remember: ultimately, you make you real money when participants end up buying or making long-term commitments with your advertisers. It is no different than PPC and other programs out there. The beauty here is that companies can get some very useful information on users via their CPA channels and, thus, that is worth money to them. Essentially, you are generating leads for other businesses so it's a win-win situation. Still, you have to earn the trust of your audience and be wary that
borderline scams could cost you major credibility.
I've seen plenty of CPA setups and the worst kinds are the ones that promise "risk-free trials" and stick people with hidden charges.. Or just make it hard to cancel a service, membership, or
autoship program. The CPA programs that work the best are the ones that offer freebies right away and, even better, have the added value of doing prize drawings. This is where survey sites are doing pretty well: you fill out surveys or commit to free trials in exchange for points that can be cashed in once significantly accumulated.. or cool swag and prizes. It's certainly an interesting income stream to cultivate...
