I'm feeling the same way, thought I'd wait it out a bit and see if they sent out another update, which seems to have happened yesterday. I have not yet installed this update, although I'm sure it won't make matters any worse, and I will when I get a chance at some point in the next few days. I can't believe they will have fixed the issues in one update and the last poster said it offered "modest performance gains" and is "somewhat quicker", not what I wanted to hear, was hoping for a complete change back to the way it was before the update. The update says that it does try to improve overall stability and performance but nothing about speed, etc.
But I agree with you about spending thousands of dollars on Apple products with the faith that their software would continue to do the same things that we've been using them for.
I also want to try to find some third party music app that serves my needs....that is translating the thousands of songs into useable, easily accessible, content. We'll have to invent one...
Keep me posted if you download the new iTunes update and I'll do the same.