I personally feel that part of the issue is that people are looking at the Surface/RT devices and comparing them with the iPad/Android tablets. You can't really pigeon-hole the Surface RT - with a fully functional operating system behind it, it's more than just another content consumption/entertainment tablet and yet with the hardware limitations imposed by the ARM architecture, it's by no means a laptop replacement.
It's something else.
I've had the iPad (the original first gen and then the iPad 2) since release. When they first came out, they were impressive devices and in my mind, the possibilities were endless. However, they were not endless - at the end of the day, the iPad (and the similar Android tablets) run what is essentially a smartphone OS designed primarily with content/entertainment in mind. That's not necessarily bad thing is that's your primary requirement - for me, the iPad only gets used as a movie player on long flights (where the in-flight entertainment may not be up to the task) and as a portable web browser. That's it.
The limitations of the iPad have always resulted in me needing to take a laptop on previous trips - even with a 64Gb model, there's no way I could use an iPad in my photography workflow (import photos, edit, export) - on my trip to Asia last year, I had nearly 50Gb of photos (including raw files) to process and this year's Kenya trip, more than that - even removing all of my videos and existing content wouldn't have left enough room. Next year's trip to Costa Rica, I'll be ditching both the iPad and the laptop and taking the Surface RT - with a photo editing app, a multi-card reader (for compact flash and SDXC) and an external USB HDD, I'll be able to do what I need to do quickly and easily.
Another short business trip to Israel this year, I could have just done with a light device capable of editing and displaying PowerPoint presentations, exporting the files to USB for the audience, and starting a remote desktop session into a remote server (using the a wireless mouse to navigate the server desktop and being able to seamlessly multi task between the presentation and the RDP session) so again, I needed to take the laptop. The next time I have this requirement, I can do it all on the Surface.
There are probably ways to get perform the above actions on the ipad and Android (e.g. using third party apps and something like a Wi-Drive) but it's by no means a smooth and easy process. In my mind, without file management and proper multitasking, the iPad is like a toy compared to the Surface which takes me back to my first point - it's like comparing apples to oranges.
As for the constant references (in various reviews and forums) to the limited number of apps in the Windows app store, I believe I read somewhere recently that the app store had more apps on it by the end of the first month than both the iPad (not counting scaled up iPhone apps) and Android tablets. Those eco-systems may now have millions of apps but they have a few years of a head start. I distinctly remember getting my first iPad and having very little on it but a couple of the initial iPad apps and a bunch of iPhone apps which looked pretty terrible.
Additionally, people are comparing RT to iOS and Android. You don't need apps for some of these things - e.g. Facebook, Twitter, Wikipedia, YouTube etc. Remember that RT is a fully featured OS with a proper browser experience (including Flash of which I'll admit I am not a fan of) - you don't need these apps on your windows MacOS environment, so do we really need apps for these on RT? On other tablets there are limitations that necessitation dedicated apps (e.g. not being able to access the file system) but not here.
Anyway, I've got a Surface RT 64Gb (with a 64Gb Sandisk Ultra MicroSDXC) on the way - this may not work out (as happened when I tried the Galaxy S3 over an iPhone) but I'm optimistic that the benefits of the OS will outweigh any of the disadvantages.
