Time to tackle 3 things:
1) No microphone, its a good thing.
One of the greatest things the Apple has is third support. Including a microphone and shutting out a dozen vendors and their unique solutions, probably not a good idea. I like the selection anyways. If I want a mic Ill clip one of the options on my lapel. Wait for after the Leopard release for an SDK, third party support is always on its way.
3rd part VOIP would be killer, but you might as well have the radio hardware and the phone features to accompany it.
2) No mail, no biggie.
I'm sure Apple will be adding more features as they come. Perhaps there needs to be a better integration of data, considering the iPod has always been used to store files. This leads me to my last issue...
3) Home on iPod.
You will see Home on iPod as was originally introduced 2 years ago, roughly about the time of this technology development. See any coincidences? This rumor will come to fruition. The eye candy to accompany it and the interface could be really, really sweet. Of course so would more memory...