"Surface RT" is not "Surface for Windows 8 Pro". Windows RT is a stripped down version of Windows designed for lower power CPUs. It's also designed to be 100% Metro based. You can't install non-metro apps on it, you can't even buy Windows RT, it has to be pre-installed on each device.
"Surface RT" is a touch-based device for holding in your hands while surfing the net and using the typical social apps.
That you even had to clarify that, on a tech site like Hacker News, speaks to what a marketing and product-segmentation disaster Surface is. So tell me - which one do I buy to get Office? That I can run office means I can run Windows 8 applications, right? It has an x86 chip in it, right? Or is it ARM? There IS one that is x86-based, right?