The iMac will, at some point, take internal design cues from the MacBook Air. The guts have always been based on laptop components. It's not far fetched to expect an iMac with no optical drive and you can already purchase one with a solid state hard drive. With the frequency most people use optical drives, the external one they sell would suffice.
Imagine how thin and fast that iMac will be. The only question is, "How soon will they introduce it?"
