The latest 1.5 software update will be accompanied by a spanking new Android app, where it will bring voice typing to the fore, allowing you to make use of your voice to respond to text messages. The software will rely on Nuance’s STT technology, allowing it to understand you rather well (keep your fingers crossed here!). Apart from that, it ought not to take too long to pick up the voice recognition details, but it seems that it will not be on par with the likes of Google Now on the handset.
Right now, it seems that the voice capability will be limited to SMS response, and to reply, you will first need to click inside the message and select the microphone icon. Hopefully future updates will bring with it other improvements along the way.