With what has been announced today, does it seem like its much softer core than all of Steve's keynotes from all the other iPhone releases?
Seems like a pretty decent update to me. The 3G, 3GS, and 4S were pretty minor hardware updates in comparison (Except maybe the 4S's camera).
Seeing as it was widely noted that Steve Jobs didn't want a larger screen on an iPhone because of app fragmentation I'd say its unlikely he had anything to do with this one.
Was Steve really involved with the iPhone 5? Sorry, but I think this is a going nowhere question. The answer is clearly yes and no and maybe. All depends on what you might consider involvement. Out of the thousands of details, many at Apple over the past few years had some involvement. Big? Decision making, leading, part of team, etc. - who knows. And, the bigger question - what does it matter?
Its interesting to consider how this keynote would have turned out if it were Steve as opposed to Cook, or whether Cook made some decision that Steve would not have made.