Just thought I'd let you know this in case, like me, you have an interface that only talks
to your mac when it's running the Kernel at 32 bit (my old tascam fw1804). And if you
upgrade to mountain lion you won't be able to boot the mac at 32 bit as I do at the mo.
Just discovered this on the apple forum accidentally when I was on the very cusp of moving
from Lion to ML! Which would instantly have made my interface redundant. Eeeek!
Here's one of the apple threads for example: Apple forum
A goal without a plan is just a wish