Although it's not confirmed which device will be the first to get Android next iteration but one thing is sure that Nexus 4 will be among the devices to receive this update. So far Google Nexus 4 didn't receive Android L developer preview but that doesn't means Nexus 4 users will not receive this update in near future. Recently shots of Nexus 4 running Android L leaked out.
These leaked shots are leaked from code.google.com website. Actually it was conversation among two Googlers who are revealing that they are currently using upcoming Android L on their Nexus 4, build number of this update is "LRW52G".
A question must arise in your mind why Google will be releasing Android L for Nexus 4 customers. Although Android L is for high end devices and supports 64 bit architecture. In a recent launching event Google mentioned that Android One devices will be getting latest updates including Android L. Devices launched at Android One event was entry level devices, while Nexus 4 is more powerful than Android One entry level devices.
Nexus 4 is featuring Qualcomm quad core 1.5 GHz Snapdragon s4 pro processor with 2 GB of RAM, Although it's not powerful as Nexus 5 but still it's pretty much capable to run Android L.