First and foremost, the KT is getting support for new types of Wifi encryption, including WPS and WPA2 Enterprise. It can also now display ebooks in landscape mode, a feature that I know a lot of readers have been wanting for a while now.
This update adds support for the (now standard) 7 languages supported by Kindle platform as well as instant translations to and from each language. You'll probably need Wifi or 3G active for the translations; it's powered by Bing Translator. Sadly, the translation service doesn't seem to work; I looked up the word lorry and it didn't provide truck as a translation (UK English to US English, doncha know).
Other new features include TTS (I thought it already had this), more sharing options, and suggestions for the onscreen keyboard. But the big one, IMO, is the new support for Kindle Format 8. The Kindle Touch can now support all the fancy new formatting found in the latest and greatest version of the Kindle format. It's not Epub, but it comes awfully close.