The first thing that people should know, because we know how hard it is for people to read all the way to the end of a multi-paragraphed article, is that those of you who already own The Witcher will be able to download all of these changes for free. So don't worry, you're not being screwed over here. It just might be rather large when all is ready to go.
Among the biggest portions of the improvements is the inclusion of voice work for 9 different languages including the original Polish and subtitles in 10 different languages. So those of you that have been dreaming of hearing the voice work in German and reading in Russian will have their dream come true. Along with that, there will be a lot of voice work added to the English version of the game, much of it to improve voice work considered bad in the original release. Roughly 5000 lines of dialogue have been updated with better voice acting and the changes are definitely for the better here.
Characters will also receive a set of nearly 200 gesture animations for dialogue cutscenes. Anyone who played The Witcher will know how frequent strange and inappropriate arm and body gestures happened during dialogue trees. These extra animations should help round out the list so that characters aren't seen moving the same way all the time and have some more appropriate movements to match their mood.
Finally, the last improvement to NPCs is in the visuals. While the same character models will be used for random NPCs, they'll all be assigned random clothes, colors, and haircuts to make them look more unique. Every time a level loads up, filler characters wandering the world will be assigned different values for each of these traits to create a pretty large variety of possible outcomes. While a few more models might be appreciated, it's certainly a big improvement. The same goes for monsters. Now you won't be fighting drowners that all look the same. They'll have the same randomness applied to their models to make sure they don't look like a clone army.
Aside from more load time improvements and other technical improvements, one of the best improved features will undoubtedly be the inventory system. Player inventory has been reconfigured to be split into two categories: alchemical items and everything else. There's also now a button to auto sort your items by further category so that all like items (scrolls or potions or books) will move next to each other and any duplicate items will automatically stack. There will also be buttons that can be used in the alchemical items section that can be pushed to highlight substances with specific ingredients so that you don't have to click through them all. This system should definitely make the stash inventory much more manageable. Combined with a small improvement to the alchemy system that will allow players to see which of the ingredients needed to create a specific potion isn't in their inventory should make the extensive potion gameplay features much more fun to use.
Finally, players will also be able to simply pick up everything on a fallen body without having to open inventory screens by simply ctrl-clicking on dead bodies. Players that wish to pick up only certain items on a body or plant will still have the option to click and open up loot windows to choose only certain items.
Along with improvements to the actual game, the Enhanced Edition will also ship with a CD of the game's music, a CD of more tracks inspired by the game, a map, the short story booklet, and of course, the game. All of this will be offered for the price of the base game. But remember anyone that owns the original can download all of this for free.
Keep an eye out for more info on The Witcher: Enhanced Edition as IGN gets it.