It has been one month since Apple unveiled a developer preview of their latest operating system, OS X Lion. And while the initial deployment was a bit rocky, Apple appears to have worked through their initial Mac App Store distribution issues. And now another update looms — and it’s potentially a big one.

Specifically, Apple is gearing up to deploy an OS X Lion update to developers that they may be classifying as the “GM1” release, we’ve heard. “GM” or “Golden Master” is a title reserved for software that is complete. But from what we’ve heard, this is only the initial Golden Master candidate. In other words, don’t get too excited just yet.

Apple has been working through many OS X Lion bugs and performance issues as they move towards the stated Summer release date. Given that GM candidates are already nearing, they definitely appear to be on schedule.

With OS X Snow Leopard, Apple released the GM version to developers just a few weeks before the actual software launched to the public. Presumably, if there were no bugs in this first GM candidate for Lion, they could stick to a similar timetable. But there probably will be, so instead I’d guess that a June timeframe will be more likely.

That would still mean an early Summer release — and potentially one before Summer technically even begins. After all, early June would line up nicely with the June 5 to 9 timeframe that Apple’s WWDC event is likely to take place this year. We’ll see — but work is clearly progressing quickly.

[photo: flickr/cheetah100]