It is not really that big a deal except when someone comes on and leaves within 5 seconds, it leaves the ones still there greeting the person that did not bother to say hi. It may be just me, but I think that is kinda rude so I have just the thing for you to do without having to do the connect/disconnect thing.
1) Open the ventrilo log on screen.
2) When the log on screen comes on, right click on the open white space that would display names if connected.
3) Select the view option.
4) Select the Server browser option.
5) Next you will see all ventrilo servers that are loaded in your personal Ventrilo.
6)Here you can select a server by clicking on it or highlighting it. Once highlighted, you can view how many are in that server, and see the codecs etc.
If you click on details...it will show you who is on at that moment. I think this box refreshes every time you open it. If not, there is a refresh button. You can even connect using that box.
If you do not want to do this, at least say hi so people there are not talking to air.