DS already has 1 ten-million selling title in Nintendogs. With combined Diamond/Pearl sales, and New Super Mario Bros., it has 2 more titles which will pass the mark this year.

But what's blowing my mind is the Western performance of Brain Training 1, and what could happen if Brain Training 2 were released in the West (I haven't even heard that this will be happening, but know of no reason why it wouldn't.)

Brain Training 1 has shipped over 2 million units to "others" regions, and is still frequently the #1 DS game on the UK charts. It has sold nearly 1.5 million units in NA, and charted in the top 20 in its 11th month, Febuary, with 70K sold, making over 2 million sales in NA seem likely too. Total WW shipments are over 7 million, and they may well reach 8 million.

Brain Training 2, however, is far outperforming 1 in Japan. Its 1.5 million units ahead of BT1 through the same number of weeks, nearly 1 million ahead overall, for a total of nearly 4.4 million units. It has a good shot of reaching 5 million this year in Japan.

What if the second game is released in the West, and similarly outperforms the first game? With a growing DS install base, and the time required to establish such a radical new brand, could BT2 do 5 million copies in the West? Or is there an oversaturation of other Brain titles already out, which would leave it dead in the water?

Most importantly, why haven't we heard anything about BT2 for the West yet, when it came out well over a year ago in Japan?

It's definately coming, They're not going to pass up a sequel to a million + selling title. As for whether or not it will outperform the first, I think it will. The first one was released considerably before the DS really took off in NA, and has mostly kept up it's sales by word of mouth. The second one would be releasing to not only a much larger install base, but to considerably more attention and anticipation. No idea what either will end up doing world wide though.

I do question why it is taking so long. Brain Training 2 came out shortly after the first one in Japan but has yet to grace our American presence. I do wonder why this is.

They likely would have given themselves more time inbetween if they would have known how huge it could be.  They are probably waiting to see how long the first can maintain sales before releasing the second in order to maximize both.

Ideally I'd like to have a chart that has NA sales for both the DS and brain age--DS sales in NA took off later than in Japan.

The NPD data is good as they come... I imagine even Nintendo uses those data in addition to units shipped. 

 But those features are still being worked out on this website so there's no convenient way to do it.

Anyhow, with such a chart, if there's anything obvious, we'll find out why.  But in any case, apparently braine age in US has only been for just about 1 year.  15-18 month wait seems just about right.  if it's an 18 month wait, that's a release just before x'mas, which is probably as good a time as any.

These games do require an extra-ordinary amount of language translation - and Europe (for instance) has a lot of languages. Writing recognition, speech recognition... some games may even need to be removed or rewritten completely.

I have been waiting for this for ages as well - "finished" BT1 a long time ago (apart from a hanful of Sudoku's remaining), and can't wait for a deeper, more complex version (#2)

What astounds me is that #1 is STILL selling in Japan - months after the second one was released. So they must be different enough to warrant having both of them. Pretty impressive I would say. 

Ah. That makes sense. Would be much harder to make sure text-based stuff works in a game like BT than, say, localizing a JRPG, and those come out on 6-8 months lag time.

If it's in the works, maybe they'll pimp it as one of their big games this Xmas.

Like they did with BT1, they added different tests for the English version to replace the Japanese oriented stuff. I think that they may be having trouble finding more tests to replace the Japanese stuff.

Personally, I thought that the BT1, English version was better than Japanese version because it had slightly better handwriting recognition (useful for shaving those extra seconds off the math 20 and 100)
and imho it had the best implementation of Sudoku on the DS (or any electronic device), I just wish it had more boards.

Also, based on history, Japan seems to reward franchises more than original titles (as long as it's not "terrible").  Sequels of good movies often do better, similarly with games.  So this could explain the success of BT2 regardless of whether it was "better" or not