Well, first of all, the apps are still too disconnected from one another.
Second, the Live Area pages, while a nice idea in theory, continue to be more annoying than useful. I waste far more time having to close multiple tabs when I don't want them open (which is most of the time), than actually viewing them. It's more hassle than it's worth.
Third, the bubbles continue to be awful. They can't be resized, they take excessively long to move/sort (especially when you need to put them on a different page), and the number you can put on each page is far too limiting. Oh, and that thing about folders, of course
Fourth, still too much reliance on touch. It's unfortunate that, despite the excellent button implementation of 1.80, you still can't do something as simple as close the lock screen without touch, or navigate the Vita's PSN Store or Trophy list, for that matter.
Overall, solid improvement, but much more needs to be done before I'll be impressed.