Motorolas design chief Jim Wicks says that Motorola is working with Google at the moment to develop pure vanilla Android phones. That means that these phones will not have any manufacture UI on top of Android and hopefully no bloatware. The phones will run the latest version of Android, could that mean Android Key Lime Pie?
He also says that they will launch during the second half of this year. To me that sounds like Google and Motorola will announce the new X phones during Google I/O in May.
Motorola thinks that bigger phones isn't better, and will make phones that are “just about right” when it comes to screen size. That probably means phones with displays around 4.5 to 4.8-inch.
I've done some videos before about the Motorola X Phone, and I believe it will be unveiled on Google I/O, because the next Nexus phone, the Nexus 5 will not be launched until October/November this year.
Maybe we will see the Nexus 7 2 on Google I/O though.