Twitter.com 2010 Redesign: What things don’t people like about #newTwitter?
My answer to Twitter.com 2010 Redesign: What things don’t people like about #newTwitter? on Quora
I also really hate the URLs forced by the Ajax-for-everything. I wish they were using HTML5 pushState on browsers that support it.
The lack of a “permalink for this tweet” is an obvious frustration which I assume they’ll fix in due time.