As far as I know I'm not using any plugins, this was a simple apt-get install of 0.6.1 from Debian (etch).
(But I'll check when I get back to my machine)
So you're probably using IMDb movie plugin, you can change it in "add window", just take a look at "Get movie data from" section in "Movie information" tab.
Is there any way of logging the transactions between Griffith and the online repositories it checks?
No, you can use debug mode (griffith --debug), but it will not give you informations about online stuff.
BTW: try to use
0.6.2 version - it's not official yet, but it fixes some problems with movie plugins (and adds new ones). This version is also "new Debian Python policy" ready
PS
I'm reproducing it now, I'll try to fix it