The unitypackage no longer includes the samples. They can be downloaded separately here:
http://www.hutonggames.com/samples.php(Note, they haven't changed since 1.3.2, so if you have those still there's no need to re-download)
We took them out because officially the Unity Asset Store doesn't allow nested unitypackages.
But this also keeps the download smaller, and lets us build a Samples download portal with more info etc.
The idea is that you will be able to browse online, play the sample in the browser, read an explanation, then download it if you want to play with it...