I'm aware of some of the limitations (no shell + file management), but since the iPad allows for more `traditional' application, it's also a thing Apple could be forced to add features developers and customers want (see, for instance, a real dev kit for the iPhone).
In case of LaTeX, you'd also need some form of `multitasking:' after you finish editing, you compile the file and then you open it in a pdf reader.
However, without a clear sign of demand, nothing is going to change ;-)
Max