what do you guys think about this page http://apple.stackexchange.com/:
The "active" button is highlighted in a way that looks like the iphone's drag button.
So the first thing that comes to my mind is that that thing is draggable.. Yet It's Not.
Yes, it is using the right affordance (to be consistent with OSX Lion).
This is slightly confusing implementation of what I think they are trying to achieve. I agree, it does look like the slider/switch control used in iOS. Sad news is, this is what OSX Lion is going to look like. They are changing the look of these "tabbed" controls. See below:
At this point, I agree it's a little confusing, considering that iOS uses a similar styling for their slider controls. Only time will tell if this was the right move on Apple's part.
As far as apple.stackexchange goes, they are doing the right thing by reflecting the upcoming Apple interface in their own design.
Update: As Jin pointed out, Apple reversed this design decision in the latest build of OSX Lion (thankfully). You can read about it here. It appears that apple.stackexchange will also be changing it to reflect this decision.
The importance of user feedback in action! :)
It's a list of links so, no, the slider UI is completely wrong for that particular interaction.
If Apple are going this way with Lion, they should read their own HIG. The Metaphor here (and the usual name for the gadget) is a Radio button, where one pushes a single button to select the item. Twas ever thus! Selecting an item by pushing it, to have it protrude is illogical.