I owned the 2003 version way back, and now own the 2010 version. I am trying to remember the changes, but my memory is somewhat foggy (I blame it on me turning 40

). I know for sure that some of the resources have changed. You can see the current Bible and devotional choices here...
http://www.heartofdakota.com/little-hands-packages.php
Any mistakes found in the guide have also been fixed. The activities, I believe, are the same. The font is a bit different. I am thinking that sums it up. One of our favorite all-time Bibles for our dc has been "The New Bible in Pictures for Little Eyes". The questions at the bottom really helped our sons to think more deeply and pay better attention to the Bible readings. The new version of "Big Thoughts for Little People" is also a favorite of ours. The pictures are vibrant, and the character lessons are such a help to us as parents for this age. HTH, and have fun with LHTH! I have done it 3 times, and I'm saving it to do with grandchildren someday! That's how much I love it. Enjoy!
In Christ,
Julie