I think both of them are there as a form of future planning, much like the extra icons in iTunes. They correspond to planned features not yet implemented.
The crosshair cursor's purpose is likely to be targeting a particular user - for example, to let them know that you are talking specifically to that person. This will probably be used in conjunction with...
...the 3 circle icons, which are likely to represent n-way audio/video conferencing. The first icon means "available", the second "available, being pressed", as in clicked on, and the third "unavailable".