Sure. I'm just saying that we need not get carried away with dismissing anecdotal evidence as completely useless. It's just useless when one attempts to extrapolate out based on limited evidence and reach definitive conclusions. But there's nothing inherently wrong with reaching some tentative conclusion based on firsthand evidence. Confidence in that conclusion just needs to be tempered pending hard numbers.
You are correct. Though I will say that most musings are tainted from the getgo - wherever your bias lies is what you're going to see. Using the aforementioned PS3 example, people who wanted the PS3 to do well will be more receptive to the PS3 skus being sold. Similarly, people apathetic to the console will see the opposite.
that's the problem with this Wii U launch, and frankly all console launches. You will have people who for whatever reason are hot, lukewarm or cold to the system, and the anecdotal evidence will taint their opinion thusly. One anecdotal account can be interpreted many different ways depending on who's reading it, and everyone's account is different.
I feel the best way to interpret anecdotal evidence is to establish a reason the masses are seeing what they're seeing, say, high shipments per week or a price slash. While it's no more accurate. It's a little bit more fruitful than "success!" or "bomba".