See I personally can't stand portables. I can never find a comfortable position to use them in that doesn't hurt my neck. The screen is attached to the controller and I tend to move the controller around a bit when I play games. As a result I move the screen which I'm trying to look at and the whole thing is disorienting. I didn't really start to love my GBA until I got the GB Player. In retrospect my DS was a waste of money. I have no use for it as a portable and playing games on it is a frustrating chore. The whole set up just doesn't work for me and I likely won't get the 3DS.
At this point the blurring between console and portable does not excite me because it seems like the direction it will go at first is just offering a portable. The 3D feature prohibits Nintendo from making this thing attach to a TV. Yeah, the feature could just be disabled when connected to a TV but I know that isn't how Nintendo rolls. Portables are also big in Japan and Nintendo plans everything around Japan. I could see a switchover where the 3DS is Nintendo's primary focus and the Wii or Wii 2 is just the casual focused gaming machine for the living room. I can see the possibility that next gen Nintendo would put the "real" Zelda, Metroid and Mario on the 3DS. Traditionally Nintendo has very clearly treated their console as the "A" platform and the portable as the "B". I could see that flipping around.
Having one platform available in both portable and home console formats is ideal because then it just becomes about the personal preferences of the user. I know other people like me that own portables entirely to play the exclusive games that system offers and that it is practically never used in a portable setting. It would nice if there was no need for that phenomenon to exist. The idea of major console game series being moved to portables upsets me. Essentially it would be like taking those games away from me. I can't play them the way I want to anymore (thinking about it, motion control upsets me in a similar way). But on the other hand, Kytim89, if consoles don't work for you anymore then you're in a similar situation where all sorts of games are effectively cut off from you. Both situations are undesirable but it has been a necessary evil for portables since matching the technology of consoles was just not cost feasible. But if that restriction no longer applies then it really is stupid and arbitrary for this game or that game to only be playable in one format.
Though stuff like this 3D screen and motion control keep consoles and portables seperate. Nintendo could always use those features to justify keeping the formats independant of each other. Of course 3D is optional since it can be turned off for all games and not all games require motion control. There isn't really anything wrong with having a handful of games that only work on one format - realistically it's no different then how some games require a light gun or an instrument - but, again, that isn't how Nintendo rolls. If they create a justification to have two completely different systems they can get us all to buy both. I figure as the line blurs between consoles and portables Nintendo will introduce more and more "unique features" to artificially differentiate between the two formats.
However the one-format concept could catch on if Japan becomes more and more portable focused and North America becomes more and more console focused (due to Americans loving their home theatre setups). The incompatibility between the two markets may necessitate a common ground where one format is used that serves both markets.