This article does seem a bit late since CakePHP 2.0 is on it's way.  However, I felt it prudent to point out a few things that I'm really happy to see in the new default CSS provided by CakePHP.

On CakePHP's website, you will find an excellent migration guide from 1.2 to 1.3 here:
http://book.cakephp.org/view/1561/Migrating-from-CakePHP-1-2-to-1-3

It describes in great detail the various changes throughout the entire application and there are a lot of them.  But I think it left out some of the most important stuff, the default CSS provided for people who use the bakery to create their websites!

One of the things that irked me in 1.2 was I had to manually update the paginator helper to display what field is currently being sorted on.  Many times I had to ensure my peers were also doing the same thing and a lot of time was wasted checking this and ensuring it was done correctly.