OK here’s my feedback:
We had three people playing (actually, more like fooling around with the screens, but we did try one encounter). I tried this out both as a player and a GM.
My impressions:
I like the dice roller. I hate the type where you have to type in things like 4D8+1D10-2MOD etc.every time you roll. Just Clicking buttons and saving dice combos is better.
We only used the type chat, which is fine as far as type chat goes, what can you say? Voice chat will be convenient when you have it up. For example in our case the reason we used type chat is because only one of us had a voice program.
The map functions took awhile to figure out. I know you have instructions but who ever reads those

Anyway the first GM finally figured how to use the map cover and reveal stuff and explained it to me. Zoom, move, and miniature moves were pretty self explanatory. The fact that the maps don’t automatically refresh for everyone when one person moves a token caused some confusion, but I think your intro says you are going to put that feature in. When I was GM I saved a message that said “everyone refresh your screen again!” and displayed it before and after anything important happened. Also, I think you should warn players that their map will appear black when it first comes up, until the GM uncovers it.
The selection of miniatures is pretty impressive.
All in all I’d rate it as an easy to use program, with some limitations, but hopefully you’ll be adding more stuff.
Since you asked somewhere on your site, my vote for the next new feature is – SOUND! - Not just voice chat, but sound effects, ambient sounds, and ability to play music.