Unexpected conversion to reiserfs

[KayAubrey-Chimene <kay@grandadventuresranch.com>]

Hi,

After a recent Sarge UPGRADE, my root has been converted to reiserfs. I 
don't recall selecting a conversion to this file system. It also rewrote 
etc/mtab. I had to reboot recently and the boot process triggered a 
manual fsck session.

Any pointers as to why reiserfs was foisted on my computer would be 
appreciated.

Cheers,
jec