: Apple has been revamping its mobile operating system about once per year since the iPhone’s release, and with WWDC 2011 featuring the iOS 5 unveiling, it’s a solid bet that iOS 6 will bow at this year’s event.

As for what to expect in the new software, the rumor mill has been especially noisy in regards to . Web rumors often aren’t worth the paper they elect not to be printed upon, but the cacophony of Maps-related rumblings make this one prediction we feel pretty good about. That’s especially true when you consider that the Maps app clearly lags behind Android, which offers features like turn-by-turn GPS directions, cached maps for offline access, and points of interest, and consider all the mapping-related acquisitions Apple made over the past couple years.

We’ve already shared an , but there are plenty of other improvements still to be made in Apple’s current software, and some rough edges that could use polishing. One minor example: iOS still offers no way to mute notifications temporarily or on a schedule (say, during sleeping hours); perhaps Apple will address that failing.

iOS 4’s multitasking support didn’t see a significant update in iOS 5, in terms of what apps can accomplish while running in the background, especially compared to Apple’s competitors. Perhaps . And maybe Apple will offer developers a new way for their apps to fetch new data (like articles, tweets, or emails) even when they’re not running.

Much attention has recently focused on Siri, Apple’s voice-recognizing feature introduced with the iPhone 4S. Siri is the rare Apple release to sport the “beta” moniker, which clearly says that Apple plans further improvements to the virtual assistant. And those improvements could touch on several areas: A most welcome addition would be the ability for third-party developers to let Siri access data from their apps, for example retrieving sports scores, tweets, or news headlines. It’s also likely that Apple could add a few more online sources to help power Siri’s knowledge, in addition to Yelp and WolframAlpha. And we’ve already listed off .