Privacy
As the GM Tool offers the ability to check for updates automatically and has other online features as well, some people could be worried about privacy. This page will contain a description of all(!) online actions the tool will do.
Automatic Update
NO Data is sent when checking for an automatic update. The tool only downloads the file http://gmtool.irian.de/version.txt and checks the number in it against it's internal version number. If the number in the file is higher, it will tell you to update and show you the rest of the text file (which contains the changelist).
As far as I know my hoster doesn't even keep a logfile, so I can't even search in this logfile and see who downloaded “version.txt” recently. I can only see how much traffic my page used (and even this page you're viewing now costs more bandwith than the version.txt file), so I really don't have a chance on checking how many people check for updates 
Online Data
When storing your characters, notes and images online, the only connection the the tool opens will be the one to your desired webserver to download your files. That's all.
I will release the source code of the tool as soon as I have a stable release, then you can check for yourself, until then, you'll have to believe me or simply check for yourself with wireshark or a similar tool.
