This is an interesting article from http://blog.wired.com/games/2007/05/nintendo_ds_and.html#more
Nintendo DS and Japan's Dwindling Shelf Space
"Our marketing people are telling me that less and less shelf space is available today (due to the increased titles.) Before, all software packages were placed so that the front sides were facing visitors to the outlets. Now, almost all the software for Nintendo platforms are displayed so only the spine of the packages can be seen by customers, and it is becoming hard for our marketers to visually demonstrate the strong appeal of these titles at the outlets." -- Satoru Iwata, president of Nintendo
And it's totally true. This is what the Nintendo DS section looks like in typical Tokyo game stores right now. There are so many titles that even as they continue to expand the DS section, they have to put games on the shelves spine-out except for a select few.
This does raise questions about potential market gluts. Even with such an unprecedentedly huge userbase, there's so much Nintendo DS software out there that it's going to be harder and harder for individual titles to really make their mark. And then of course you run the risk of the market being flooded with sub-standard software. Then again, that's exactly the reason why Nintendo instituted the quality control checks and final authority over game releases that have become industry standard practice -- to prevent the sort of product flood that killed Atari.
What will eventually have to happen is that this particular store will likely cut back on their PlayStation 2 section, which currently takes up three or four shelves this size, and expand the Nintendo DS area. It is worth noting that I didn't even see the PlayStation 3 section anywhere, which some of my friends later agreed was true in various stores.
Well, we all know DS is extremely popular in Japan, but some stores lack of PS3 section is new for me.