You can't change the past. No matter what Sony has done, to get into their current situation (and their games division, frankly, is one of the better performing parts of the company at this time), all they can do right now is make good decisions, and climb back toward decent profits. I believe they are doing just that.
You don't have to have big marketshare to make decent profits (although its usually preferable). You just have to have enough to justify your console's existance to the 3rd parties. I would say that Sony is still well within acceptable limits, in that regard, although they clearly need to do something next year to retake marketshare. Doing something drastic in the short-term, however, may very well be a decision they cannot afford to make. A price cut drastic enough to compete with the $300 X360 Pro, and its little brother, I think is out of the question -- perhaps until Sony begins to manufacture PS3s with 45nm Cell CPUs (which they have stated would be happening mid-2009).
Microsoft's situation was completely different coming into this holiday season. They needed to do something drastic, or they were going to fall to 3rd place. That picture was pretty clear, around mid-year this year. They had significant delays getting the Jasper (their own 65/65nm unit) out the door, so I'm near positive that's going to hurt them pretty severely next quarter. They were producing Falcons that actually cost more to make than the Falcons last year did (they used higher quality solid capacitors, to reduce RRoD issues starting around July) up until late October. That was *well* after the cut. That means there are *millions* of X360s that have been sold at a significant loss this quarter. If they could have cut the price earlier... they would have, I guarantee you.
I believe that both Sony and MS have been making good decisions in this regard, and I'm surprised at all the media hate (for Sony). Sony deserved the media hate last year, not this one, IMO. The media is going so overboard with it this year, its almost as if they are doing some sort of stock tape-painting for future Sony stockholders.