Is it known whether or not Unity will have the option to act like the current custom gnome menus (Applications, Places, System)? From what I've seen they've designed it to take up the whole desktop when the menu is opened.
Also, the File, View, Edit menus, will it be possible to have them stay within the application itself rather than be displayed within the top panel?
It is already known that you can choose whenever start your session using Unity or the 'good old' Gnome Desktop.
This is possible ( at least in the 11.04 Alpha 1 ) by selecting the Gnome Desktop in the session dropdown on the login screen.
(In case your system has not graphic acceleration enabled ( i.e. compiz ) then the default session will be the old Gnome one.)
Also it is possible to remove the global menu behavior by removing the package
indicator-appmenu( there is not graphical settings up to now )Also they assert that Unity launcher won't be moveable. ( http://www.omgubuntu.co.uk/2010/12/ubuntu-unity-launcher-wont-be-moveable/ )