Credits, Facebook’s nascent virtual currency of sorts, is getting a simple change tonight. The company is marking down items in its gift store from 100 credits to 10 credits, and reducing users’ corresponding number of credits.

Facebook users who are worried about losing the last zero off their credit supplies can take comfort in the fact that they can still buy the same number of gifts as they had before. So if you had 200 credits, you’ll have 20 credits now — but those 100-credit gifts are now 10 credits a pop. Prices, adjusted for the change, are the same $1 per 10 credits.

On its face, one less digit in the system makes counting up credits simpler, and makes each credit seem more valuable to users. But there’s something more happening here.

The move comes as the company prepares to introduce a new part of the credit system for third-party developers in the coming weeks. Most Facebook users only know credits within the context of buying gifts — only a few have access to another part of the credit experiment, where friends in a network can give each other credits for things like funny comments. The changes today show the company trying to refine the credit system now, before third-party developers start using it — with the expectation of stable pricing.

And, as you can see from the Terminator head in screenshot, the change also comes at a time when Facebook is testing out sponsored virtual gifts, that let you earn credits instead of paying for them. A simple, stable pricing system is probably what potential advertisers would like to see, as well.

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