Lumia Denim will be released in Q4 2014 for Nokia 830, 930, Icon, & 1520 with Windows 8.1 Update 1 per this article:Full of features: Lumia Denim Update - Conversations : now part of Microsoft.
Verizon testing will put this into Q1 2015 i'll bet.
A little late Nokia Lumia - Here Comes Denim Firmware
