Rick, basically the RT can only run apps from the App Store... and it is the same that is on W8's Start screen. Many are just like Apple's and I suppose other tablet app stores.
The 'real' product can run both the 'metro' apps that the RT can run but also probably most Windows apps. So this would make the Surface (not the RT) more like a netbook or ultralight laptop. I'd suspect cost to be in that range as well. The RT, like any other tablet I guess, dependent on app store for apps and a decision point in the purchase of it.
As for the Windows store I've seen many that 'echo' what I can get on my iPad. I loaded USA Today onto the W8 machine and like it (it is 'different' from the iPad app). A few others too, but in general, none are worth having in my estimation on a 'real' computer, especially if one has any tablet.
Price and the market situation at the time of release will be a deciding factor for many.
Looking at the iPad vs. the Surface RT it is hard for me to compare. I don't know app sizes nor the OS space taken. Case, well the stand is nice as is a keyboard possibly, but these are also available for the iPad, and probably any Blutooth keyboard would work, don't know.
I don't know if I'd want a keyboard for my iPad, that is unless I need to do some real data input and the iPad was the only way I could do it? For what I use it for, very little data input is required.