I have Mathematica for Students v5.0 and I am so glad I do as it has helped me enormously over the past year and will continue to do so for the next few years. It costs $140 for the student version, which is worth it if you really need it, like I do. However, there are features in 5.1 which I really need but I couldn't figure out how to download the update. I finally figured out that this isn't a standard free update, you actually have to purchase it. The price, which definitely surprised me, is $100, only $40 less than buying it for the first time. Maybe if this were v6 or something and there was a whole slew of new features and things were really different, but there is only a limited number of changes made. Admittedly these are some major changes that greatly improve the program, but not $100 worth. Of course then there is the Pro version; I can't imagine how much that must be to update.