It does matter in the fact that moving 180k is not solid when you are in a competition with two other companies, what you posted above is almost verbatim to what Nintendo was saying when the Gamecube was getting thrashed by the PS2 and the Xbox, only difference is Nintendo was turning a massive profit on the Gamecube.
Does all this sales jibba jabber really matter? I mean, seriously, the PS3 is a high end machine. Not everyone will buy it because of it's price point. It's a given. From the looks of it, it is still moving a solid 180,000 units a month which may not be the numbers the Wii is doing at its price point but still a solid base that is growing.
Now, if the PS3 wasn't selling at all we'd have issues.