Currently no prefs to control, and is redundant with dock icon.
Let me ask one question before I take the time to look into it. Did you take multiple accounts into thought? I have more than one account and I'm sure other people may as well.
Added menubar icon showing activity.
What people are looking for is a menu bar icon which is switchable (off/on) and allows quick access to calling/sms. They do want to see if there is any new activity, however they don't want it to only do this.
I probably will not approve of code to add a menu bar icon until the above is covered. I do not care for a menu bar icon because I already have way too many on my computer and I wish that some of the things which has a menu bar icon didn't such as growl. That is why I haven't developed one myself.
I am not saying I'm not going to accept a menu bar icon for VoiceMac, I'm just saying that I won't accept a half done job.