On the 30th November 2015 Photoshop got an update, making the latest version Photoshop CC 2015.1
In terms of what’s been updated the answer is a lot. In the past updates have been maybe bug fixes and the odd addition to a tool. This new update addresses a lot of previous issues as well as adding smoother work flow.
One the main differences is when you first open the program. You are now presented with a completely different screen that shows a mini file browser of recent projects.
There has also been more touch enhancements and a new modifier panel has been added.
The art boards that were recently introduced have been updated also making easier to work with.
A full list of items in the update are:
Reintroduced the Oil Paint filter
New “Graphic and Web” workspace
Support sRGB export with new Export As options
Ability to resize the Export As dialog
Improved PNG interface in the Export As dialog (for exporting to PNG-32 or PNG-8)
Saved file type and quality settings between Exports
Improved stability of Device Preview connection, and added more troubleshooting options
Set type layer position on canvas (X/Y) in the Properties panel
Option to skip transform when placing Smart Objects on canvas
Added an option to save to Libraries when pasting a Smart Object from Illustrator
Improvements to Copy/Paste/Drag between documents, clipboard and CC Libraries
Improve the display of artboard names, allow them to be turned off
Artboard and marquee snapping improvements
Added artboard preference for matte color and border type
Align command now works with single selected layer within artboard (artboard is implicitly selected)
Artboard custom presets now show up in the Artboard tool bar/property presets menu
Prevent Locked Layers from being auto-nested in artboards
Allow artboards to lock position
Added keyboard modifier (shift) to determine if layers get added to bottom of groups
Better default shape stroke value (1 px instead of 3 pt)
Added 16pt as one of the preset values in the font size drop-down
Hyphenation now defaults to Off
Added several items to Designer Favorites in Glyph panel
Maintain selected glyph when switching fonts
Selecting a single glyph on canvas selects the glyph in Glyph panel
Added option for “diffusion” to Healing Brush, to reduce artifacts in some situations
Improved baseline alignment of many dialogs and widgets
Improved document presets with new iPad Pro, updated presets with DCI 4k, 8K, and moved HDTV up the list
Disabled the “no layers selected” error when clicking with Move tool outside the canvas
Dramatically reduced file sizes for 16- and 32-bit PSDs when “Max compatibility” is unchecked
As you can see a lot has been done in this update