The big theme of the release is integration - we can now automatically import activities from Google Calendar, Tripit, and Dopplr, we have added an iCal feed so you can view whereyougonnabe information in your regular calendar, and you can set your Facebook and/or Twitter status whenever an activity begins. In general, a big challenge with future location is how to create data as easily and automatically as possible, and this is a big step forward in that regard.
We also made significant changes to the way that we calculate interactions and decide what to notify you about, which I have come to realize is a very hard problem, as I have got more into this (which is good, as it is harder for other people to copy what we are doing).
You can read more specific information at our whereyougonnabe blog, or watch the following video for an overview of the new features:
whereyougonnabe July 2008 release overview from Peter Batty on Vimeo.
We also have several more detailed videos explaining how to set up and use the new features. Our big focus for the next release is on the user interface, an area where we have a lot of ideas and plans that we are excited about.