Lately it has been rumored that the next major update of Android will be called Key Lime Pie, and some of the latest rumors also claims that Android 5.0 will be released in late October, and that the operating system will be highly optimized for older phones as well.
This means that Android phones with only 512 MB of RAM should be able to run the brand new OS. This could be important in the fight against the increasing fragmentation of various Android versions on different mobiles.
The potential release date for Key Lime Pie comes at the same time as the rumored Motorola X Phone and the Nexus 5. These phones are rumored to be released with Andoid 5. If this is true or not remains to be seen.