Working with a new user of Inventor last week he was complaining of functionality he had in MDT that did not exist in 2008 Inventor, having the ability to move parts inside assemblies from point to point without using constraints. Autodesk Inventor 2009 to the rescue once again, this seems to becoming a very common theme.
A Grip Snap tool for precise moves and rotations has been added to the existing tools to move and rotate one or more components, subassemblies, and work geometry in Assemblies.
The icons automatically shown in a ribbon represent the translational and rotational options available for an entity you select. Tooltips describe the behaviors they represent.
The Heads Up Display provides visual cues for the next action, a place to enter precise values, and can provide feedback about the translational and rotational degrees of freedom for the entity you select.
On the Context menu which is a right click away you can click Done to accept the actions previewed, or Commit and Ground to accept and ground the entities you manipulate with the Grip Snap tool. This tool has a lot of possibilities be sure to check them all out.