I don't see the problem with autosave... sure, there should be a way to turn it off, but there's no great reason to not have it on by default. why should the user have to remember to save all the time when the computer can do it automatically? people forget to do things all the time. you aren't special.
the problem is many of Lion's features aren't plainly a move forward. let's start with the improvements:
- autosave and versioning are good, useful to everyone
- FileVault 2 is good, much improved over the original
- Mail looks and works a little better
- AirDrop is useful
- AirPort renamed to Wi-fi in the menu bar, which is less confusing
- Mail, Contact, & Calendars in System Prefs is nice - one location for importing and managing online accounts
but then there are a bunch of step backwards:
- Launchpad is pretty useless
- Mission Control replaces All Windows Exposé and Spaces, loses many features of Spaces, isn't a replacement for either, and it uses more space and looks more cluttered as a result (though not a big problem for a desktop)
- Full Screen: good idea, bad implementation. no multiple screen support, can't switch between application windows or view desktop using Exposé, slow animation
- active window gray is lighter than it was in SL, and it's too close to the inactive window gray (which I think is the same as in SL)
- iCal and Address Book took two big steps backward in appearance, AB in usability
- more gestures, but I feel like I have to relearn them (more like learn them in the first place) since they've changed and aren't as intuitive
- bunch of extra useless, slow animations
- feels slower overall, even after turning off a lot of the extra animations
compare this to Leopard, which featured BootCamp, Dashboard Web Clips, Stacks, Quick Look, Spaces, and Time Machine, which are all steps forward...the only bad move I can think of off the type of my head is the overly reflective Dock.
Lion obviously has stability and compatibility issues, but that's a problem for every new OS and shouldn't be counted against it.
I ran Lion 10.7.0 on my 2009 2.26 13" MBP for 2-3 weeks while my MP remained on SL. I've since switched my MBP back to SL, even though many of Lion's features (e.g. Full Screen) are meant to help mobile users. the execution is just poor.