rally, that is about what I would expect. poor you!
I skipped Lion.
I remember the Snow Leopard upgrade. Printer drivers were not up to date from the printer manufacturers, and it took months for some!
in many cases even later on the drivers were not updated, at all, because they were outside support.
etc etc etc.
OS X lets you take an image of your existing installation with the onboard tool Disk Utility. I would do that. Put that image on a separate hard drive or partition and install the upgrade.
Following a checklist, test every single possible workflow you have been using
And if I were on 10.7 already, I'd check whether I need any of the
"new features" of 10.8.
I'd wait longer than 2 weeks, too, before I'd test 10.8.
That's from a professional point of view.
And that's how I treat my personal Mac at home.
I will upgrade to 10.8. But I'll wait. Say till 10.8.1. yup.