A Motorola smartphone bearing the model number "XT1058" appeared in FCC filings last week. The "designed & assembled in the USA" device appears to be equipped with NFC, LTE 4G and geared for AT&T's network (GSM 850/1900) – could this be the long-rumored Motorola "X Phone"?

Now owned by Google following a $12.5 billion deal, many have expected Motorola Mobility to become the search company's hammer for pounding out cutting-edge Android smartphones. Google itself admitted it doesn't want to become a handset manufacturer though; however, this wouldn't be the first time a company said one thing and did another.

There have been a bountiful assortment of rumors regarding the Motorola X Phone (or perhaps XFON), some of which claim the handset will be exclusively available for AT&T, feature a bloat-free Android install and a 4.7-inch screen. Others have suggested Motorola's secret phone will ship with Android 5, be unbreakable -- even flexible – unprecedentedly user-customizable and possibly even come in wood. Heck, it may not even be a phone at all but an overarching device initiative.

It seems the only thing missing from the X Phone's rumored features is "magical", but Apple may very well have that trademarked.

Despite the varied and sometimes far-reaching rumors, what Motorola Mobility will produce is expected to "phenomenal", or at least that's according to Google chairman Eric Schmidt. May onlookers have high expectations of the Google-Motorola Mobility partnership, a historical merger which has likely helped propel Motorola's mythical X phone to new heights of absurdity.

It's worth noting Google I/O is later this week -- perhaps we'll learn more in a couple of days.