At the Partitioning step of the live installer, when you select Manual, the Edit option can be very confusing. If you select any given partition the window will show. The "use as" field. Now this is alright if you assume the user is going to want to format this partition, but sometimes you dont. I run into this problem because I have my entire disk already partitioned and I only use the manual partitioner to mark the root mount point and the mount point for my home folder. It goes like this, I first mark the root mount point. Here it makes sense for there to be no default cause I want to reformat to ext3, so I select ext3 next to use as and I check the box to format. Here comes the problem, when I go to edit another partiton and I decide it should mount to /home there is no default. I have to select ext3 next to "use as" as if I want to format it was well. I do not want to do this at all that partition has valuable data cause its my home folder from other distros. Granted there is a format checkbutton, but having me select what filesystem it should have gives the impression that it is going to be formated. I figure a compromise might be to allow there to be no default when editing an partition, but when a partition has already been marked as the root mount point then the default should be the detected filesystem on that particular partition. Its something to think about at least.
Currently we 'mimic' debian-installer. But there is re-designed manual repartitioning [1] which has not yet been implemented.
Can you test debian-installer on the server cd and check if that pre-offers correct file-systems?
[1] http://