In fact there isn't a single market of consumer electronics where the most expensive option is also the best selling.
Except there is regularly- the gaming market. PS2 was the most expensive(tied for the most v the XB, always more then the NGC) option for the majority of the last generation and it decimated the competition. When the 360 launched it became the most expensive system and until they hit supply issues it was also the best selling system. 360 games have topped the chart numerous times since its' launch, also the most expensive options on the market. Oh yeah, currently it appears that HDTVs are going to outsell SDTVs
this year. Not some far off future date, that is what is happening now. DVDs also outsell VHS and have for a long time, despite their being more expensive for most of the last ten years. Your assertion that the most expensive product in the electronics industry does not ever sell the best is simply not true in the least. Having a higher price point isn't going to help you out any- but it certainly does not mean that you will not be the best selling platform within reason(I am focusing on platforms as that is what consumers are buying here, it isn't like if you buy a Panny LCD you can't watch a lot of what a Bravia owner can- that IS what the console market is).
In terms of overall marketshare I think there are a few too many varriables to make a good call right now. As a 360 owner I can honestly say that I think MS has done a horrible job with their launch in almost every regard. They still lack an exclusive killer app, their library is very weak, they have serious issues with reliability and they failed to capitalize on their early launch window demand. With all of that said- you can say the same in every instance about the PS2. The one thing you can't say about the PS2 is that demand tapered off much sooner then expected in Europe and in the US and there never was any demand in Japan at all. If MS manages to hit 10Million before the PS3 launches it means little in the end despite what they may think. Sony outsold MS by more then that on a global basis each year of this generation since the XB launched. If they had hit ten million by now and were building a mass of mindshare in the more mainstream market then they could have had something going for them- that isn't happening and the tumbling sales numbers reflect that as of now(the PS2 is outselling it fairly easily despite ready availability of the 360 at this point). MS has already lost Japan- that isn't good considering they aren't even facing any competition yet. Their sales aren't very good in the US and Europe either- they were too supply limited and then they manage to ramp production right before the slowest period of the gaming year and they do so with NOTHING in the pipe to sell systems until we get into Q3/Q4 timeframe when the hype maching will be on for the Wii and PS3.
Sony has their own issues to deal with, the one I think matters the least is the launch price. Is everyone poor? I don't think so. Certainly there is an enormous percentage of the population that would never spend $600 on a console- but there are easily six million on the face of Earth that will- and largely do so with a smile on their face as they walk out of the store. After Sony gets past the initial launch, scales of economy should allow them to drop the price significantly without hurting their bottom line too much while the general consumer who wouldn't think of dropping $600 will see a great deal when the low end model hits the $300 price point. Sony certainly has to deal with a lot of issues this generation- but the launch price is certainly not close to being on their major points. How many people dropped more then $600 on ebay for a 360? It is a non issue- they are all going to sell out and there will be a lot of let down people looking for one, $600 in hand.
Sony has to deal with Nintendo in Japan- that is a serious threat. I think in a realistic fashion they are safe. The only potential N has for reclaiming the throne in their home market is if they can manage to land DQ as an exclusive- not likely. With the severe technical limitations and the tiny storage medium it isn't realistic to assume a next gen DQ game will manage to fit on a DVD9. It isn't like DQ pushes the boundaries on visuals very often(you could argue ever although DQ8 is IMO one of if not the best looking PS2 game), but the scope of the games aren't likely to be friendly to such a small medium.
Nin looks strongest in Japan, and they could end being huge in the mass market if they can pull off what they are trying to. I am not banking on it. Not that they won't do what they are saying they will on their end- the thing is most people who don't play games now aren't interested in them. Unlike luring customers back to theaters, there isn't a huge portion of the population who used to enjoy that past time and then quit- they are trying to pull an older demographic into an entirely new medium. I wish them the best of luck, and if they can do a fraction of what they imply it would be fantastic- but their goals this generation are far more difficult to achieve then either Sony's or MS's. In the US and Europe gamers are going to be turned off by the lack of third party games and the perception that Nin is for a milder audience- something that Nin is working very hard to reinforce with their focus on the Wii.
MS can turn things around if they can push out some killer apps this holiday season and capitalize on the lack of PS3s to fill demand- I see that as their last window of oppurtunity to truly exploit being very early.
Sony is still the dominant player in the industry- they need to focus on keeping the hype up and timing some killer apps for when they are likely to reach certain production/price points. If they fail in this, they make the others jobs a lot easier.
Nin needs to fire on every cylinder and tout their price advantage and back it up with some real titles. Current rumors indicating a Wii launch without Mario or Smash Bros does not bode well for them. Early word of mouth takes a long while to overcome- good or bad.