Funny thing is, I have a 3DS XL now and gifted the 3DS to my brother for finishing his apprenticeship but I couldn't get him to play with it, nothing really hooked him. No SM3DL, no Kingdom Hearts, nothing. As a last resort I bought him Pokemon white and now he plays the 3DS like 10 hours a day and got addicted to street passing. Long story short, Pokemon is a force.

To not derail the thread, let me say that I don't think the audience for Pokemon is into preorders. It's either kids or parents, who buy it for their kids and have no idea that preordering is a thing. The 3DS will probably not be as succesful as the DS and even go just as far as the PSP did in sales numbers, but those numbers will not be achieved because of piracy. 70 million units can be considered a healthy economy for video games, when the platform hasn't been cracked.

The PSP sales declined here because it was mostly used as a media device. Them the iPhone came out and was a much more attractive media device and the demand for PSP dropped off the cliff.

When the 3DS gets an actual Pokemon game and other RPGs, then it will start to see longevity until Nintendo announces another handheld.

No way the 3DS will follow the PSP trajectory. Sales aren't as brisk as many would like and it won't match the DS in any territory. But I think these are new times in the industry. Those stratospheric Wii and DS-esque numbers won't be replicated for a good long while.

Everyone beat me to Pokemon, so I must use the second trump card.
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...I just realized that Advance Wars is criminally underrated. D'oh!

I think the 3DS will get a big holiday boost (as will every console) and it will also benefit from some sort of Wii U integration. At least, I hope there's some way for the two to wow us by working together. The two can feed off of each other.

having worked at retail, I can honestly say that the number of people using the psp as a media device was just a tiny fraction.  The iphone release actually had almost no impact on the psp's sale figures.  PSP sales figures were pretty similiar durring it's first three years of existence.  The release of the DS lite a year after put a little dent into the psp, but the big decline is psp sales in the west happened around the same time the DSi came out.  

Nintendo doesn't do handheld to console connectivity very well.  Remember zelda and the four swords?  *shudders*

I thought Four Swords was a shining example of how to do handheld to console connectivity.  O_o

Unfortunately, I do.  I remember the "Tingle Tuner", too.  But I hope this is another idea whose time has finally come.  Motion controls were attempted in the past and always sucked.  Then, one day, the time was just right and it was a huge success.  Maybe the time is right for some 3DS integration.  If it doesn't happen now, it never will because portable consoles are probably going to be a memory next gen.

I'd like to add that the three big Mario games seem on track to sell more copies than any game that has been released for PSP. And at a lower install base to boot (for now).