So far v12 is unusable for me.
Beside the bugs and instability, the interface more cumbersome the previous versions.
When you said you were going to create a single window IDE type interface, we did not expect that was meant for each and every suite you had open. When develop across at a minimum of three suites per test log (script) this interface design hinders our productivity far more than it helps.
And why can you no longer right click items in the suite panel? Having to select the item and click the option gear then select the option you want is a complete step backwards from what it was prior.
[EDIT] This is a bug only relating to Mac OS X 10.6.
It maybe this is better for some for different reason or maybe some users feel the same but I would really like to hear what other users feel about the latest version.