I am interest in trying to make the incremental file size a little larger.
Currently its fixed to 5Mb as far as I can see.
You end up with so many files, they are hard to manage, fsck, deleteing is a problem sometimes also.
I was thinking if you could pass a variable/switch to request it to be say 650Mb or something (to fit on a CD) , or even 100mb would make 20 times less files.
I had also thought using a sub directory for each incremental run, using the date stamp or serial number just once. You end up with a sort of tree (just 1 level) and you dont get out of control directory sizes. This would make analyzing/cleaning up much easier. It might even enable you to keep filename lengths a little more tidy, and it may even work with a samba share at some stage (which I think the long filenames of the archives breaks currently).
I guess this comes from using duplicity so much. Its great !!!