I'm really a fan of Lion, but I'll admit that Preview is a little weird. I don't really get the whole "Duplicate" thing and no "Save as..." is annoying. The same goes for Text Edit. The whole Versions and auto-save thing is just different. Anyone have a good understanding of the whole thing?
Versions and autosave is brilliant. No more having to worry about something going wrong and you forgot to save, or accidentally overwriting files you didn't mean to in apps where the APIs supported. For a full analysis of it read this:
http://arstechnica.com/apple/reviews/2011/07/mac-os-x-10-7.ars/7