Applied the latest CS6 Mac update last night and the next startup it took forever to load. At one stage the Premiere icon was bouncing up and down with "application not responding".

I can report however if left alone eventually the machine cycles through all your plug ins (re-indexing?) and the next startup is at the normal speed.

I've had slow startups after an update before but nothing on that magnitude. So if you do the update, fire up Premiere, walk away and get a cup of coffee. All will be fine (eventually).

Repair disk permissions with Disk Utility (included software).

If you're unfamiliar here's some instructions:
Disk Utility - Using Disk Utility to Repair Permissions (http://macs.about.com/od/applications/ss/firstaid_3.htm)