Wow — just updated my Treo with the updater for my Cingular Treo 650 and the results are pretty incredible. Available memory on the phone went from 4 megabytes to over 10 megabytes, thanks to the changes in the Palm file system). What does that mean? In the old filesystem, files took up a minimum of 512 bytes (even a one byte file would occupy a block of 512 bytes, leading to lots of “dead” space). In the new filesystem, the minimum block size is 32 bytes, meaning that the new Treo uses its memory much more efficiently.
It also claims improved voice quality and improved battery management; I’ll test those out and see if I notice anything.