In an innocuous press release today, Apple announced the motherlode: at its Worldwide Developers Conference keynote presentation next week, the company will announce its two next-generation operating systems and a new “cloud services offering.” At the conference next Monday, June 6, we will see the finishing touches on Mac OS X Lion, as well as the brand new iPhone, iPad, and iPod touch OS, iOS5.

Lion is the eighth major release of Mac OS, and the first since 2007’s Leopard to announce major new features. Lion is bringing aboard new features like Mission Control for managing your desktops, Launch Pad for launching apps in an iOS-like manner, and Versions, which is a new way to manage saved files. If you’re interested in more information about Lion, we did a walkthrough after the beta came out. Since Apple has already announced and previewed many of Lion’s new features, we can only expect a few bonus features to be showcased at WWDC next week.

Apple's Motherlode: Lion, iOS5, and iCloud All Being Announced Monday

Even more secretive is iOS5, something that has been talked about ad nauseam but never even announced by Apple until now. Rumors are that iOS5 is going to be the savior that brings iOS back up to speed with the other mobile OSes feature wise, and will include a brand new Maps app, revamped notifications, widgets, and more. How many of these rumors are actually true? Nobody really knows, so get your popcorn ready and hope that Mr. Jobs brings an early Christmas to iOS users and iOS5 isn’t just a small, incremental upgrade.

Finally, we have iCloud. What exactly is iCloud, you ask? Well, all that Apple has said is that it’s the company’s “upcoming cloud services offering.” This could mean several things; most likely it is a combination both of MobileMe, a cloud storage “locker” for your files similar to what Amazon offers, and possibly a “scan-and-match” music streaming service. While Google and Amazon have both launched streaming music services over the last couple of months, the catch is that these services require a painful upload process that can take days for users with slow connections and large libraries. If Apple had thrown its weight around, it might have been able to secure rights to stream its own copies of music back to users, allowing iTunes to scan a music library and then “unlock” the streaming versions of the songs based on their local copies.

We’ll be following the WWDC all week next week, so check back next Monday morning to find out which of these rumors come true.