You probably know all the major changes for 1.10:
- New Enchanting/Herbalism Bags
- Priest Changes
- Armor Sets (<--New Blizzard Page)
- Final Destination Flight Paths
- Gold for Quest xp at Level 60
But let's take note of the little things that might get overlooked (from the patch notes - if you've digested them already you can skip this, particularly since the patch notes have been available for weeks):
- Shift-R will now reply to the last person that you sent a tell to rather than the last person who sent a tell to you.
- Various tooltips updated.
- Reputation will no longer be gained if a pet kills a monster without aid.
- A new level 52 druid quest that takes place in Un'Goro crater has been added.
- (Druid) All shapeshift forms can now use equipped items.
- The drop rate for Essence of Air has been increased.
- Added support for widescreen video resolutions.
I also noticed:
- A lot of changes that appeared to be fixes to problems, exploits, griefing, etc..
- A lot of changes to other classes, particularly Hunter
- A lot of changes that should affect add-ons and mods (See This Link for a list of mods that broke with 1.10)