Facebook Credits will become the mandatory payment method for games on the social network next month. With that timing in mind, here are suggestions from top game developers on how to maximize revenues with the virtual currency.

Use Discounts To Increase Short-Term Monetization

Popcap, developer of Facebook games Bejeweled Blitz and Zuma Blitz, sees strong sales from its “happy hour” Friday discounts of virtual goods purchased with Facebook Credits.

However, Popcap’s Jon David cautions, while discounting is a good strategy, extending discounts for too long (such as an entire day) often leads to a drop in revenue in subsequent days.

For example, after customers take advantage of the discount offerings, the market for additional purchases may drop off in the days following the sales period.

David recommends experimenting with discount length and pricing to find the optimal levels for increasing revenue.

Beware of Under-Pricing Virtual Goods

To increase revenue, Mike Sego of Gaia Online (developer of Facebook’s Monster Galaxy) offered this advice, which may sound counter-intuitive at first: “Make sure that you’re pricing things appropriately high… it’s easy to make items too low of a price.”

Through testing, his company discovered that pricing virtual goods for significantly fewer Facebook Credits did not necessarily lead to significantly more paying customers.

Just as many gamers are already accustomed to paying $60 for a single console game, high value users might be willing to pay $30 or more a month in Credits for high quality Facebook gaming experiences.

Sego added:

It’s tough to price things at the right sweet spot, but when in doubt, it’s safer to go slightly too high rather than too low, as that frees you up for more opportunity to experiment with discounts, lower the prices later until you find a sweet spot.

He did note that this pricing advice will likely reduce adoption to Facebook Credits, “but could result in higher overall revenues.”

Avoid Promotional Credits

According to Jan Miczaika of Wooga, developer of numerous top Facebook games, using promotional giveaways of Facebook Credits has not proven a successful strategy for increasing monetization.

Instead, it “created a lot of friction in the ecosystem, introduced billing headaches and, as far as we can see, did not have an impact on overall monetization neither positive nor negative.”

The problem with promotional offers, from Wooga’s perspective, is they don’t seem to add new paying customers or introduce the idea of paying for virtual goods to new users.

Instead, Miczaika told us, “There were simply free Credits slushing around in the system, which did not add value.”

Facebook developers, what strategies have been most successful for you?

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