There are some awesome little things that I've noticed in the first week or two of using Photoshop CS6. They're super useful in my web developer workflow, and they're just little things that really add up to save me a ton of time.
With the marquee tool, a tool-tip shows the dimensions of the currently selected area.
Holding Shift when dragging a new guide snaps that guide to the ruler marks.
When creating a new guide from the View Menu, it re-uses your previous orientation selection (Horizontal or Vertical).
Control + mouse scroll will scroll the image horizontally.
I can finally paste a hex color (with the # ) into the color picker.
Alt + click on the Layer Styles triangle now opens (or closes) all layer styles.
These small improvements to my everyday workflow are far more important than whopping huge new features that I (the web developer) probably won't ever use.