At present, the Wii U's RAM is split in half; 1GB for the OS, 1GB for gaming. While this is still more than twice as much as the PS3 and 360 have available for games, more could be a big help as games continue to become more memory intensive.

Over their lifespans, the Xbox 360 and PS3 had more RAM freed up for games by Sony/MS optimising their OS's; could Nintendo do the same with Wii U?

While it's not ideal, I think it might help matters if they allowed developers to disable certain features to make use of more ram.

Yes but ultimately is there a need? Would ports utilise the extra ram? Unlikely as most ports never bothered to use most of the Cell processor.
Exclusives could use the RAM but again, is there really a need? Considering it looks like both the PS4 and nextbox will use 8GB of RAM, freeing up an extra 256mb (if that) seems a waste of time.

Windows 7 is barely using 1.5GB of RAM on my PC, I find it hard to believe the Wii U OS actually needs a full 1 GB, there must be room for optimization. Unless part of that is reserved to run apps alongside games (does it even do that?).

Pretty much this.

It runs other apps yes. 

Still don't think it requires 1GB though.

It's easier to use extra RAM than an architecturally challenging processor though. A little bit more wiggle room could make the difference between, "a cut down port is possible" and "porting would be impossible."

I doubt it will happen myself, but its a possibility, no? Didn't they do it with the 3DS?

I suspect that 1GB is being reserved either because Nintendo isn't sure what features it wants to add to the OS, or snt sure how efficiently it can add intended features. So yeah, I can easily imagine more RAM opening up for games as Nintendo zeroes in on the features it wants fr Wii U.

Of course, the other side of this question is how badly game developers want more RAM.

If they could free up another 0.5 GB that would honestly help a lot I think.  That way they could have half a GB for textures and a full 1 GB for the system.  

This would allow noticably higher textures than PS360 and enough system RAM to get by.  Still though if anything it would probably only give the Wii U an extra year before all support is dropped due to it being too weak.

Yeah I suppose it would make things easier, and maybe certain things more console specific e.g. DLC could harness such a thing. Is it possible? Certainl, however I would be surprised if it was used.