Perhaps the user experience is mostly there, but I would not describe it as fantastic.
For me the pain starts when you click in the "share what's new box". It's the first, most basic operation and it's bad.
For a start, I click on the left hand side of the screen the whole card jumps to the center of the screen. (at about 15 fps!) Why? Why does it move?
Not only am I forced to shift my attention from where I clicked, but everything on the screen reflows drawing my attention all over the screen.
Not only that, the icons all change size and shape, and a bunch of extra stuff is added. If you wanted a completely different dialog box, how about just a button that says "new post"
Next up lets have a look at "People I may know" box on the right side of the screen. I see a friend, and next to his icon is a button that says "Add". When I try to move my mouse over to click it, it's hidden behind a popup window that "rolls" into place (badly) and I have to check boxes to put them in specific circles.
Sure, as a developer I can see that this is an optimization of a two step process, but it breaking some basic rules about what a button is. To me its jarring and clunky. Is just weird.
I dont know what would be better, but how about some "circle" icons that I could drag my friends face onto? Too weird? How about a drop down at the top of the card that dictates what circle a new friend goes into.
I could go on and on and if anybody at Google is interested I will!