What's not to like? The fact that as soon as you copy, email, or otherwise clone the file all those versions are gone from that clone. (Technically, those intermediate vesions are not actually saved in your text file but in a hidden area of your disk, so when you copy or otherwise share the document, the links to the intermediate versions are not retained and the versions are not embeddable into the copied or shared file.) The rationale is noble: This way, all those internal drafts aren't accidentally available to others, saving you from embarrassing or sensitive accidental disclosures. Remember how the track-change feature in Office documents led to such inadvertent revelations when it was first implemented?
But this safety feature also means you can't amend your own document elsewhere or let authorized members of a group continue to work on it and keep those tracked versions in place. Apple needs to add an option to copy, email, and otherwise clone a document and keep those versions in the clone. Yes, please continue to exclude these versions by default, but give me a way to carry them over when I want to share.
Lion letdown 4: Whole-disk encryption
Lion fixes a longtime gap in Mac OS X by letting you encrypt entire disks, as well as your Time Machine backups. Before, it would encrypt only files in each user's account folders. That covered most of what users worked on, but not everything. You can also format external disks to have them be encrypted.
What you can't do is encrypt an external disk after the fact -- just the startup disk. All those thumb drives and external disks you use? Sorry, to encrypt them you have to first format them. If you can encrypt your startup disk at any point, why not be able to encrypt any disk after the fact, especially considering that Lion lets you unencrypt a disk at any time using Disk Utility? Disk Utility or the Security & Privacy systems preference (where you encrypt the startup disk) should be able encrypt and decrypt any disk at any time.
Lion letdown 5: User configuration profiles
Using Mac OS X Lion Server -- a $50 add-on to Lion -- you can create configuration profiles for both iOS devices and Lion-based Macs. These profiles can both determine various settings, such as email accounts, and restrict user access to various iOS and Lion capabilities. IT should like that in a Mac OS X Server-based department, especially because you can provision and update profiles over the air.
But let's face it: Most Macs are used in home and small businesses that don't have IT departments. Many of the policies you can set via these profiles would make sense in such environments, but Mac OS X Lion Server is not friendly enough for this group of users. I believe Apple should update its Parental Controls system preference to include at least some of these configuration profiles, making it simple to set up and install to other Macs on your home or office network -- without having to use the Lion Server interface, even if it is much simpler than a Windows or Linux server.
Plus, bringing these capabilities into Parental Controls could also be part of bringing Apple ID management into a simpler management interface. That way, you can set purchase restrictions for your kids or employees without needing separate Apple IDs; at the least, you could manage those separate IDs from one place. With a mix of shared and separate multiple Apple IDs often in play for Apple's various online stores, iTunes Home Sharing, and soon iCloud, it's becoming a management mess for the rest of us.