I like it better if 100% of the software on the device operates under the same constraints, so the developer of some app that I really need/want can't decide "no, you need to be in desktop-alike mode for this to run, because I just don't feel like dealing with tablet mode". It's basically the same problem as allowing multiple app stores, in that it'd fragment the experience and leave me having to choose between "do what the developer of this app wanted, which isn't what I wanted" and "don't have the app". I prefer that everyone has to deliver software the same way, under the same constraints, for predictability and user control of their environment (that is, I want the device to work like a traditional tablet, period, so I prefer that developers have to treat it that way, as it results in the device always working the way I want it to, for all software that runs on it)

And in fact, I can currently choose the experience I want if I decide I want a typical multitasking desktop—by putting down the iPad and going over to a Mac (or Linux, or Windows, or FreeBSD machine, or whatever). Or, to extend the "I like a tablet that becomes things, modally" way of thinking about it, by putting the iPad in Remote Desktop mode and connecting over VNC or SSH or RDP to a traditional desktop or server.