As a Kickstarter supporter of the Roll20 VTT, I got my Beta invite yesterday and got to spend some time with the interface. It has a lot of potential, it has handful of quirks, and as I had to remind myself, it's still in beta.
It is beyond simple to add tokens and maps to the interface. Just type a search term into the search box (I used "kobold" and it comes back with a bunch of tokens you can grab from the net. Drag it and drop it onto the map area and you're done (unless you want to resize or such).
The same can be done with maps. It searches online directories with free gaming maps, and again, it's as simple as drag and drop. Then comes the map resizing, and the first quirk.
The few maps I dragged and dropped did not fit the default "map space" or whatever it is called. They weren't all that huge, maybe 12-15 rooms and corridors, but I couldn't enlarge them to the point that their grid matched the size of the VTT grid. That is going to be an issue, and one I assume will be addressed at some point in the beta,as I am sure it's not just an issue for me.
Another quirk / issue is with the marker for the maps. I like using whiteboards and markers for my campaigns to do a quick and dirty diagram / map of what the players see. With Roll20, the moment I release the mouse button as I'm using the marker, the pointer resets to no longer be a marker. So, back to the interface, click on the marker in the menu, draw another line - rinse and repeat. I'll be bringing this up on the forums, as this is more of an issue in my mind than the map issue. It's almost a game breaker. It's possible I'm missing a solution, and if so I'll post it if / when found.
Tabs for the different "boards" or maps is a great way to bounce back and forth between locations. Spot on.
I haven't tried the music / sound effects yet, not have i had a player log in yet to check the video / voice.
I'm just trying to feel Roll 20 out at the moment