I agree with Iavor on this one. I use Haskell professionally as well, and I'm actually quite fond of what it leaves out in terms of both syntax and semantics, as opposed to what it adds. Whether it's pragma protected or not, I just don't see the point of complicating the language with such a seemingly minor feature. Also, as pointed out before, the tuple-sections feature interact badly with this, and the treatment of commas in lists and tuples being different is a source of concern.
If it's added, however, it should definitely be pragma protected as I'm pretty sure if I ever have extra commas lying around it's because I inadvertently deleted something or made some other cut-paste error. I'd like GHC to keep telling me about those in perpetuity.
-Levent.