If you’re unfamiliar with JH, it allows you to learn Japanese writing, language and culture, and Kanji via lessons, practice sessions, and quizzes, in addition to having large Japanese dictionaries available in multiple languages. Of course, a free trial is available.
Since its original release, new features include:
* resetting lesson and vocabulary review data
* sharing any word or phrase via email, SMS, or social networks
* developer RSS feed for quick updates
* follow on Facebook and Twitter @JapaneseHub
Regarding the speed increase, this is seen as a reduction in the time to load pages the first time. Restructuring the data in the app has reduced page load times to the point of not even being noticeable.