I've been working on konqueror to address and solve all (I hope :-) the problems that were preventing a smooth and fast navigation in "IconView" mode.

So I've investigated over qt, kio, libkonq, konqueror/iconview and finally managed to get some patches working. You can find the results on:
http://robotics.dei.unipd.it/~koral/KDE/kflicker.html

Short index of patches:

• 02: bugfix: solves bugs 67866 67793 (repaint when entering/leaving window)
• 03: bugfix: saves N (=items in directory) icon paints (speeds up browsing of large dirs (2x.. 3x faster on a 600 files directory!!))
• 04: bugfix: sometimes appeared an "unsorted" frame before the final drawing
• 05: feature: disables background clearing when switching from an URL to another to smooth navigation
• 01: feature: buffered QIconViews, this solves the flickering at-its-roots using the well known back buffering technique (note: every IconView will have a backbuffer. If you have 256MB of ram or more you won't notice the loss)

Thanks goes to David Faure, the main author and editor of the cool code I've been looking to.