Despite my better judgement, I went ahead and upgraded to Mac OS X 10.7 Lion yesterday morning, about 30 minutes after it became available on the Mac App Store. While it was installing, I read John Siracusa’s amazingly in-depth review on ArsTechnica. While I agree with most of the criticisms, especially about the lack of retention of spatial information in the Finder, I have to say that Lion has hit the ball out of the park. I’m totally comfortable with almost everything they are doing – most of it will make OS X easier to use and support – and make the OS get the hell out of my way when I’m trying to do something. I’m particularly enamored with the running program/process management pieces, where Lion will silently quit unused applications (that support the state-saving magic) and relaunch them when they are requested again, as well as *not* quit applications when there is a glut of available resources. For most users, this will mean a better experience with the OS and with applications, and it will serve as a pretty good carrot to get developers to support the new APIs and move into the future.

I ran into four gotchas when I upgraded:

1. Lion disables support for older Kerberos ticket types. This breaks my employer’s AFS tokens. Add allow_weak_crypto = true to the [libdefaults] section, and single-des tickets work again
2. AFS 1.4.x, which I was running, doesn’t work well with Lion, even after Kerberos is fixed. Upgrade to the Lion build of OpenAFS 1.6pre7, and you’re golden.
3. TimeMachine over SMB has broken for me, and I haven’t been able to get netatalk 2.1.5 to work with Lion yet.
4. The globalSAN iSCSI Initiator has some issues – while it will let me mount Solaris 11 iSCSI volumes, I can’t reboot without kernel panics and it seems to destroy battery/sleep management. Uninstalled for now, as I don’t need it on my laptop.

That’s it so far. I’ll post more as I run across issues and gems.