Tomax: there's already a shortcut to hide the category column. I can easily add a shortcut for the note list if needed.
While it can be disturbing at first to move from iOrganize 5 to iOrganize 6, most beta-testers now love the new user interface, and it should also be easier to use for new users.
iOrganize 6 was indeed designed to look like Mail, which probably features the best possible user interface to search/collect/sort: no drawer, everything visible on screen, easy to drag&drop a note in another category.
Well, probably not the best user interface for _all_ users/uses, but let's say for most (as Mail, iTunes, iCal, iPhoto, XCode... are all using a similar user interface).
To anybody: don't hesitate to send feedback by email. All comments are read and taken into account. Features requested by several persons have more chances of being taken into account, so don't hesitate to send feature requests even if they seem obvious to you.