1) The "Show/Hide future tasks" filter is now available if you use the start-date field but don't use the due-date field.
2) There is a new filter for subtasks. You can choose to have subtasks either nested or flattened out by default. Previously, subtasks were always flattened, except in the folder view where they were nested. Now, you can select which behavior you want.
If you choose "flattened" you can always re-nest subtasks on a case by case basis by clicking the icon adjacent to the task. Be careful if you use the nesting behavior. With nesting turned on, subtasks will always be hidden under their parent task. This can make it very easy to forget about a subtask that has an approaching due-date if you don't toggle the parent to look inside.
Unfortunately, I preferred the old version where they were always nested in the folder view and always flattened everywhere else. That made complete sense to me. Now I have to keep pushing the toggle button to replicate this as I go from folder to main. Oh well, you can't please everyone all the time...
Jon, You should be able to keep it exactly the way you had it before. The behavior is entirely backwards compatible. Just go to the Folders view and set the filter to be nested. Then set the filter to be flattened in all the other views. The filters are stick on a per-view basis, so once you set this up, you'll never need to toggle it again.