Working with objects in Illustrator is, first and foremost, about creativityif you can imagine it, you can draw it. But it's also about efficiency and reducing repetitive tasks.
In the old days, Illustrator required you to draw everything by hand. Multiple sizes of objects needed to be drawn individually. If you needed duplicates of objects, you copied and pasted and lived with the increased file size and the higher processor and RAM overhead. When the duplicate objects needed to be modified, you edited them one by one or copied, pasted, and positioned them all over again. Warped objects were hand drawn, with tedious tweaking of paths and careful adjustment of direction handles. Lining up and spacing objects required guides and temporary boxes used as spacers. If you wanted 3Dwell, you didn't do it in Illustrator.
Illustrator's 3D effects aren't the end-all and be-all of 3D workthey still don't compare to dedicated applications such as Maya, Bryce, and Lightwavebut do they need to measure up to those applications? Most 3D work is of the simple nature of extrusion or rotation. Why use an entirely different 3D rendering application, with a completely new user interface to learn, for simple work? Those applications have valuable roles in the modern creative workflow, but when only simple dimensionality is needed, you can do it more conveniently within the familiar environment of Illustrator. From there, Illustrator's tight Creative Suite integration enables rapid deployment of the 3D objects to InDesign, Photoshop, or GoLive.
Even the way in which Illustrator fills objects is improving. What more natural, more familiar way to color is there than simply coloring between the lines? Live Paint in particular is a huge productivity enhancer when used judiciously. With the right artwork, it takes your mental focus off the objects and places it where it belongsin the artwork.
As Illustrator matures, more and more of the menial tasks are becoming automated. You'll find that you spend less time working the mechanics of a drawing and more time being creative.