From what I've read, this sounds like the combination of the regular 3DS/3DSXL and the Circle Pad Pro with an upgraded CPU and microSD card support. The custom home menu sounds cool too.
For anyone who is interested in some pictures, here you go :
Front view :
Back view (flipped) :
It sucks a bit that you wouldn't be able to play the exclusive games for the new 3DS on the old 3DS, but what can you do? At least it's better than Xenoblade Chronicles not getting a remake. Yeah, I heard that Xenoblade Chronicles is one of the exclusive games that will be available for the new 3DS systems. That also got me a little pumped up because it's a Wii game that I've always wanted to get/play. I've heard a lot of good things about that game,
Hopefully there is an exchange program like
@D4rkDragon mentioned (which I highly doubt, but there should be game stores that you can trade it in or something) or at least some sort of discount offer for people who already own a 3DS system. That is, if the new 3DS and 3DS LL systems are indeed coming to North America and Europe.
I also hope developers don't drop support for the 3DS though, just because there is a new, more powerful 3DS,
I want to continue seeing major game releases for the current 3DS/3DS-XL/2DS systems,
There's even a rumour saying that you'll be able to transfer files to a PC without even removing the SD Card from your 3DS.
I heard that it'll have a feature that allows the user to transfer media files to and from a computer.