Backgrounds! You can now play as a band with a background, each having bonuses and penalties.
Guardsmen
Merchants
Thieves Guild
Rangers
Wizards
Northerners
Pit Fighters
or even just plain old vanilla (all existing save games will use this)

Potions! You can now buy (and craft via the Alchemy skill) potions of:
Healing
Strength
Speed
Energy
Fire
Courage
Poison Gas

There are 5 new rare magic item types
Glasses
Crown
Chalice
Horn
Mask

And 5 new magic item abilities
Vampirism
Ethereality
Thorns
Poison
Terror

Balance changes for Easy Difficulty - before it was very hard to get XP as the battles were so easy...
Big bonus added. (To a lesser extent, likewise for Normal difficulty)

Bugfix - sometimes you couldn't do an Active Skill (Like Defend) if you had the exact number of AP required.

Pursuing enemy on the strategic map could get very jerky - fixed to be a bit smarter about the number of times it needs to recalculate the route to the enemy.

Traits - this bug has been in there for a while - everyone was getting 5 traits, when it should be much fewer... Oops!

Various minor tweaks and fixes.

** EDIT **
Performance tweaks! I've cached a lot more graphics, so you should some speed improvements, especially when flicking between screens in a town, and when loading a new combat.