Thanks a lot. I can't even go anywhere on line without a pop-up window telling me what I already know: Your update sucks.
I woke up this morning thinking the charmingly mellow James Taylor song "Carolina in My Mind," started watching a video of it on YouTube, decided to buy it in iTunes, opened iTunes, got prompted to update software, and now iTunes opens only to crash immediately, so I can't buy it, and I can't even get to the YouTube video anymore. If I see the phrase "Plug-in failure" a few hundred more times, I may lose my mind... or my 25-year-long love for Apple.
ADDED: This and today's cool Google doodle have motivated me to try Chrome as my new browser. Safari had been crashing repeatedly even before the current update. Unfortunately, I still can't get Flash to work.
UPDATE: By the end of the day, Apple had an update (or updates) that appeared to solve the problem.