Apple on Friday released a Gold Master (GM) build of Mac OS X “Lion” to developers. It’s no great surprise, since Apple already announced July as the release month for Lion, but it’s a good sign that Lion’s release may come earlier in the month rather than later.

A software GM is typically the final release before software ships. So barring any show-stopping bugs, this should be the build that consumers will be able to purchase from the Mac App Store once Lion is available for retail purchase.

Apple will make Lion available for sale through the Mac App Store for $29.99. Apple counts over 250 new features in Lion, including Multi-Touch gestures, Mission Control and full screen apps.