Those not following the implementation of concepts from http://d7ux.org/ here is a quick summary of the three main areas:
- The header toolbar from http://www.d7ux.org/header/ is in Drupal 7 already (in the form of toolbar module). Icons are missing (still to be discussed, see http://drupal.org/node/13911#comment-1701664) and customizable shortcuts (http://drupal.org/node/511286) are still under discussion. You can override, revoke permissions and disable the header if you don't want to use/see it, but it is enabled in the default profile by design. There are also some other smaller follow up issues you can find and contribute to from http://drupal.org/node/484820
- We are hard at work on the overlay. You should be able to use it without the admin theme and toolbar (or with a different admin theme and/or toolbar), but it is aware of the admin toolbar. There seems to be mostly some positioning issues to overcome here, see http://drupal.org/node/517688
- We are working on the admin theme as well, which Young Hahn christened the Slate theme. The looks of the theme when not in the overlay is still to be refined, but themer reviews are showing good results. Again, this would be the default admin theme for Drupal 7 but will be configurable. See http://drupal.org/node/484860
There are lots of things going on improving user experience even in relatively large scales additionally to these three, but given how close the code freeze is, I am trying to get attention to these three, and especially the overlay and the admin theme, so we can get them in sooner then later.