I'm curious about their implementation of NLP. This has enormous potential as a teaching tool - the biggest hurdle to getting more out of a package like this on first use is not knowing how to interact with it. However, I had had similar expectations of Alpha, and was greatly disappointed. though full of witty easter eggs and stocked with a rich variety of datasets, exploratory queries proved sadly frustrating.
Here's what I want to see in version 9 (laugh now, realize I'm right later): Kinect interaction. Perhaps unwittingly, Microsoft have just launched the next great peripheral and it seems intuitively popular with the public in a way I haven't seen for years and years. Now, imagine you've generated or imported a mathematically-specified 3d object in M., and imagine it inside a bounding box with handles on the vertices and local minima/maxima. Multi-point, multi-d interactivity would be both absorbing for students and potentially extremely productive for professionals, without requiring significant retooling of the core.