you *could* run a newton emulator on it, but they won't let you. It's closed and locked down according to all reports.

There are all sorts of worries about what someone could do with a bad app on a cellphone (anything from just blasting out cell pings and wifi blasts that would stop any other phone nearby working, to emailing your address book to China, to setting up calls to the Honduras for six hours every night running your bill up in thousands!) so the network operators are very strict about what they allow (also they usually provide the help desk if your phone stops working, so they want to be very sure what's on there and what it is doing ... at least Java is a fairly restricted and safe playground which is why it's on so many phones!)