Mobile versions (Android, iOS, Windows RT)

Tablets and consoles are different, but the problem is that the tablet OSes stated in OP are still different OSes that require porting work, even ignoring the different hardware architecture (not talking about computing power). Thus, people really can't say "tablet" without specifying the specific OS in relation to the architecture---a Windows 7 tablet is vastly different from an iPad on so many levels. And of course add to that specific HID requirements on top of hardware architecture, computing power, memory, and required storage space.

Tablet OS's are as different as desktop OS's, but that's what's great about Unity: it supports Android and iOS the same way it supports Linux, Mac OS and Windows. I don't think that Windows RT is really relevant right now, but if it becomes popular Unity will likely support it. While there are some differences between Unity for desktop and mobile OS's, the difference between Unity for iOS and Android are minimal, and I think that for the purposes of this project the differences between Unity for desktop and mobile are minimal, since it's unlikely that the project will use advanced features of Unity which aren't supported on mobile.