I've done tech support and quite often if the solution isn't obvious I can't say how long it will take, or even give an update of progress until the problem is just about solved. If I know how long it will take then I know the solution. And given bethesda's history of giving out updates on progress of DLC that turns out to be wrong. I can see why they are more tight lipped this time around.
If you are a subject matter expert in the target system, the libraries involved and fully understand the implementation details, that is a pretty sweet place to be making project plans from - those plans would include a timeline.. Basically the Bethesda PS3 coders know all necessary things intimately. Perhaps that Sony has been purportedly called in is an indication of just how bleak Beth's PS3 team views the situation.
Why can't Beth give us updates? I think its more a question of why won't Beth give us updates.
I guess because they know DG will never be satisfactory and there is only one more update to provide: that DG is not coming. The longer they can play out this drama the more they can appear to actually be doing something.
If they were actually doing something then weekly updates would probably be pretty easy. I don't think 30 minutes of the lead PS3 dev time to prep a summary report thats passed from the PS3 team to GStaff, which is subsequently reviewed, demystified and appended to the sticky is that resource intensive. Especially when you're talking about a fan base that is quite rightfully pissed about continued substandard treatment.
Beth may have the most brilliant PS3 team on the planet for all we know, but they have been given a difficult task - make Gamebryo run on the PS3. Only one studio has managed this before and they were notably absent from the opening credits.
As for PS3 support, I think we really saw the end of support after 1.4/5 time frame. I mean they left a patch out their where potentially thousands of people had the water glitch and never bothered to update/fix it. That is notwithstanding the delay between 1.1 and 1.4 patches, then the blackout after 1.6 was released for XBox/PC.