I don't mind the concepts, but because they aren't done very well in Lion, they can be very...unpleasant to deal with. For instance the Resume function, which re-opens windows in an application the exact same way you left it, can be exacerbatingly aggressive in an app like Preview. I use Preview a lot to read PDFs and view images. On occasion I can open hundreds of files at a time. Now, in Lion, if I forget to close each and every window, guess what I get when I open up Preview the next time? Yep, hundreds of windows. And if you for some reason manage to block this feature (you can do so by locking a certain folder in /users/Library) and update the OS and forget to redo the locking of the folder, you get every single window of every single file you've ever opened with that app.
No offense Apple, but I like having actual control over my setups, thank you very much.
Autosave and Versions is actually one reason many companies are no longer deploying new Macs. Many tech companies and agencies with sensitive data have a zero-copy (other than specifically archived) policy/NDAs. Autosave and Versions cannot be turned off. This means that you get unwanted versions saved regardless of whether or not you're allowed to. As such, those companies cannot afford to put Lion in any aspect of their development environment, and thus, no longer deploy new Macs or update them past 10.6.x.
Versions is also somewhat of a PITA for writers that normally do their best to control revisions (usually by naming them in a specific way that Versions does not allow for). It's also a pain for anybody that codes, since it creates eleventy billion backup files of the eleventy billion project files used to create an app (and on an SSD where garbage collection can't kick in because of constant OS activity, that becomes a major problem once all NAND cells are written to and have to be erased and re-written to in order to accept new data, causing major slowdowns). I know very well this slowdown issue - World of Warcraft's patching method shuffles files around an insane amount of times, and I've had to reformat my SSD (zero all data), after copying the contents back to my HD several times because the NAND cells all got written to via patching/"optimizing" and my write speed slowed to <1MB/sec because of it.
Like I said, I don't mind the features of Lion per se. What I do mind is that I have no control over what the OS is doing with my files. Apple is more and more turning Mac OS into iOS, and sandboxing everything they possibly can in order to deprive the user of any semblance of control over their computer. That's the reason I refuse to get an iPhone and went with an Epic 4G for my cell phone. The lack of user control and UI clutter when many apps are installed just made me absolutely hate iOS, and because that's what Lion really is, an overblown iOS, I despise it too. There's a lot to be said for user control, and Lion has almost none. Hell I can't even get visible scroll bars back in Lion. I'm stuck with the iPhone's scroll bars, and on white/grey backgrounds they're not only hard to see, but damn near impossible to click without major fuss (they don't appear until you scroll the screen up or down (or side to side), which defeats the purpose of having a scroll bar in the first place!
No, Lion's awesome under the hood, but it's a piss poor excuse for a desktop OS in terms of user friendliness/control. And unless things change in that regard, this may be the last Mac I ever get. It's sad when Windows 7 has more user control than OS X. Very sad indeed.
FWIW I give Lion kudos for one thing - its graphics drivers absolutely blow Snow Leopard's out of the water, no contest at all. It's like night and day the differences in the two versions of OpenGL.