To give a short and simple answer for beginners who do not understand this yet and have not encountered a linux operating system before, linux does not use the same types of programs as windows.

Long answer:
Just as your windows program will not work on a mac, a windows program will not work on linux or vice versa unless you have an emulator or virtual machine. The maemo linux-based operating system has even more restrictions, where a linux program has to be "edited" so that it works fully and looks nice on the tablet devices. Thus far, an emulator/virtual machine has not been created or "ported" (a term used to describe the editing of a linux program to make it work on the tablets) because of hardware restrictions, time restrictions, and (I'm sure) limitations in the open source nature of the maemo operating system.