Lion

A quick note about Lion for interested clients:

Lion represents a radical new beginning in our interface with technology. It's exciting, and it offers many new advantages. It is a significant upgrade.

As with all major operating system upgrades, PsiMac recommends scheduling a consultation with us to verify and test all important software and plan the upgrades.

Before upgrading, it is imperative that you have a working, up-to-date Time Machine backup. To mitigate any possible downtime, this is good advice from John Gruber:

[R]ecommendations for installing major Mac OS X software updates:

So, in short:

1. Do a complete backup clone to an external FireWire drive.
2. Test that the backup is indeed bootable and up to date.
3. Unplug the backup drive.