There’s good news and bad news. The good: Skype 2.0 for iPhone [iTunes link] lets you make calls over 3G. The bad: After August, you’ll need to pay for the feature.

That’s right: The most yearned-for feature of Skype (Skype) for iPhone, making calls over 3G, is finally here. The new app just landed in the app store, and by all accounts the 3G calls hold up fairly well.

Here’s the catch: After August 2010, Skype will start charging a “small monthly fee” for use of the 3G calling feature. You heard that right — even though you’re already paying AT&T (in the U.S., at least) for your data plan, Skype is throwing in an extra fee. At this point we’re not sure if the move is Skype’s own doing, or if the network operators had a hand in trying to make the Skype app a less desirable option.