Answer is: a)

or

c) Nobody has spotted it yet (or at least kicked up a stink about it), so it's a timebomb waiting to go off, or

d) Nobody knows if this is right or wrong because the whole GPL and binary drivers is still a grey area and you'll get radically different answers depending on who you ask

Personally I think the binary modules are stifling development on the Nokia tablets. The ability to create your own kernel is an essential freedom of Linux that's only partially being implemented here -- you have to use a single version of the kernel in order to remain compatible with the binary kernel modules. (I guess you could backport some technologies but that's extremely hard work, and certainly not as trivial as compiling your own kernel from scratch.)

Can you explain your thinking?

Just as you can have binary modules from nvidia and ati on your desktop, you can have binary modules for the wifi and battery on the tablet.
The source of the kernel for the tablet is open source, otherwise there wouldn't be the custom kernels with usb host mode and so on that the community makes.

You can also have a binary of an OS ...
For me it is obvious the Nokia cannot be interested in opening the ITs. Why should I buy a new device if even the old one gets the newest updates.
Ok, there are people like me who think different. My next IT like device will support an OS similar to Ubuntu Mobile. I dont want to get fooled a second time.

The binary graphics drivers are 'binary blobs'. They NOT binary-only drivers. The actual driver (kernel module) is open source. It just hooks into the binary blob, which is a chunk of cross-platform code that's also used under Windows.

I've been explaining this elsewhere on this forum. AFAIK you can't simply keep module code secret. The modules will have to be compiled against the kernel headers, so you've got GPL code included there. And if GPL code is used, it's a derivative work, and therefore must also be licensed under the GPL.