New Field List Task Pane
Another addition to Access 2007 is a new version of the old Field List dialog/toolbar.
Besides retaining the old functionality of adding fields based on the record souce, the new task pane adds a couple of new features. For starters, you can now see which table are the fields coming from. Instead of a plain list, the Field List will show a tree of table and their respective fields.
That's nice, but minor. The big advantage now is that you can add fields from other tables and we will fix up your record source and ask all necessary join information as needed. This allows you to build your forms and reports without having to spend some warm-up time in a query builder or to be going back and forth between browse, design and the record source query builder.
Even further, with the new Layout Mode, you can add new fields and do all of this while viewing actual data. For example, this will save some precious time when autoring reports, which is the common place where people generally are pulling data from a large set of tables and queries.
As you can see in the picture I linked above, the new Field List task pane is complex data-aware, and will allow you to drill down to specific "sub-fields", like attachment file size and type.
Finally, a new cousin on the Field List task pane is the New Field task pane, which gives you some canned fields that we believe will speed up your app building time. You can now drag-n-drop these fields to tables, forms and reports and just start plugging away.
(06/14: Fixed typo.)