Nice points. I can't recall exactly how much memory is freed by garbage collecting now... IIRC I managed to see the GC in action one time only
I know something else, don't know if this could help... Before launching Midori browser, I had 5 megabyte of free memory, after launching it showed 50 megabyte... I'd would like to reproduce this kind of behaviour without having to open/close an app. I've tryied with DebugOn logging but can't spot exactly what does happen in this cases.
If it sounds quite pointless, sorry about that, it was just an idea...