Via Dave Winer, a link to this post from a woman who's tired of hearing "it has to be easy enough for my mother to use":

I'm so tired of people talking about how their mother wouldn't understand something. I've been hearing this for 20 years, and it's sexist and ageist, and wrong and unfair, and how about let's get rid of this offensive idea. I'd never say that about my mother, who has a PhD, and is pretty smart. I certainly wouldn't want to encourage her helplessness! At one point I leaned over to Tara Hunt and expressed this sentiment. Then I realized that she's a mom, and said so. I wonder how many mothers were in the room and how they feel about always being held up as the paragon of cluelessness.

It's not about being smart or stupid. It's about the level of usability that is typically not built into software. Recall this post I made on our excellent adventures with the Media Center PC we bought. My wife and I are both software developers, and were willing to go through the pain of setting that up. It's not that "my mother" wouldn't be smart enough; it's that she would actually be smart enough to call BS on the usability and send the thing back. I linked to this post from Doc Searls a few days ago, where he related the following:

Add to this the sad fact that audio/video sales showrooms are a confusing mess. One guy who works for one of the big-box retailers recently told me the return/swap rate on flat screens exceeded 50%, because too many people are baffled beyond endurance by the complications of hooking them up, and the results afterwards.

Are all of those people idiots? No, they just have better things to do with their free time than ponder a confusing mass of cables and ports. Software developers - and apparently, most hardware manufacturers as well (with the notable exception, IME, of Apple) seem to have a "the more the merrier" attitude about possible configurations.