New:
EXR import and export

Improvements:
SVG import and export: massive improvements
Layer mask, clipping layers, adjustment layer masks: Complete rebuild of combined masks is now delayed (better interactivity). Until rebuild only visible parts are rendered.
PDF import and export: support of linear and circular blends
PDF export: support of transparency (PDF 1.4)
PDF export: perspectively distorted text and vector layers are now saved as vector graphics
OpenType, Mac OS: support of OpenType features
Rotate Document: in picture mode all image layers will be rotated physically
Rotate Document: "Crop" is always enabled
"Assign Color Profile" and "Convert With Color Profile": Now with the option "Linear Brightness (Gamma 1.0) " (if possible with the active color profile)
32 bit images: better support
Gradient tool: the last applied gradient is stored with the layer
Color Filter: now with checkbox in the Attributes palette
Icon bars, modal dialogs, Windows: can now be used (important for zooming)
Layer tool, rotating: layers are now always rotated using the coordinate system of their group (useful in perspectively distorted groups)
Lasso tool settings: nor with icon bar for adding and subtracting
Measurement tool: now with unit and dpis
Bit depth of documents: can be recorded as action
Browse: faster saving of browse file
Middle mouse button, Windows: middle mouse buttons is activating the moving hand
Text settings: if there are different attributes inside the selection, the UI will show them as tri state
Chromatic aberration, adjustment layers: the Chromatic Aberration can now be used as adjustment layer
Convert Layer to Lasso, Convert Lasso to Layer: new 2 separate menu entries
Save Layer: saves now all active layers
Color list: can now save all selected colors
Text fields: Command+/Ctrl+click and drag changes value
Text fields: mouse wheel changes values (Shift and Ctrl/Command modifies step size)
Color range control, Hue/Saturation and Color Filter: adjusts mouse cursor to location
PNG export: smaller files by clearing transparent areas
Curve Creation: Shift forces line creation
Curve Creation: additional context sensitive mouse cursors
Web Export: clicking in document windows sets position of the preview
Attributes palette: visible part of list is no longer changed after rebuild
Stamp tools: now with tablet support
Setup Guides: turns on "Show Guides"
Color Editor, Mac OS: now with color picker
Save Page (s): now with single page mode
Screen output, images: faster
Plugin support: improved
Harmony: The color dialog "Harmony" (accessible via context menu of color fields) can be scaled now
Tool Bar: better support for more than 2 columns
Curves: now with HSV