Moving forward, we are going to deeply integrate with Steam's awesome social features. And yes, you can do things like Voice Chat! We've also got initial revisions of Private Chat and "Invite to Game" working.
Here is Valve's post: https://steamcommunity.com/updates/chatupdate
In the next version of BZT (testing now):
Click on a friend's avatar
* Private Chat - available on friends
* Add Friend / Remove Friend - now use Steam's friend list
* Invite to party up (from Social Page)
Clicking on your own avatar
* Steam groups can be accessed via "Group Chat"
* Your friend list can be opened "Friends [34]" the # is the number of online friends
* Invite Friends - invites all online friends to party up
From your friends list in Steam
* You can invite friends to your network party
Social Page
* Friends, Recently Played, ... lists now have online status indicators for friends
* There is a link to the Blast Zone! Tournament community page right on the social page
Additional improvements in build
* Improved chat bubbles in lobby
* Rank up/down notification has been improved
* We've reduced the memory required for the game a bit
* Fonts sizes will better match between western and Asian languages
* Level 20+ EXP issue has been resolved