I think Apple is running out of ideas of innovation in an operating system and are just re-naming things after making them look a little different. Kind of disappointing. But then yet, what else can one really do to an OS....
One thing they could do is make the OS have an artificial AI that you interact with. Now that would be cool! Tell the Mac to open up Text Edit and have it type what you say like a secretary would, or tell it to Google something and it instantly opens up Safari and does the search for you. Ask it what the weather's like and it opens up The Weather Channel in Safari and tells you the current conditions + forecast (using voice) while you look at it.
Ones imagination is the limit with this.
You're all over the place. First you moan about it, then you concede there's only so far you can go with an OS, then you go into a bunch of AI stuff and other ideas that would be a total usability nightmare (especially at this stage.)
Yes, sometimes there's not a whole lot of new things you can do to an OS given the *usable* technology that's out there. Walking the line between "new" and "familiar" is difficult to do at the best of times. OS X Lion is not a complete ground-up rewrite, nor is it meant to be, nor should it be. It simplifies, it streamlines certain tasks, etc. That's why it's like $30 and not $130. You can't even buy a decent dinner for two for $30 these days. And if you can, it's gone. You ate it. At least with OS X you're getting not just an application but an entire OS that'll last you around two years and probably provide some lasting enjoyment.