Nintendo is in a much different situation now than they were when the 3DS launched. Their marketshare and mindshare is fairly low, although mindshare is growing due to their mobile initiative. But really, the main difference is that the NX is supposed to be the combination of all of Nintendo's efforts onto one platform. They've essentially said as much several times over the past few years.
It would be disappointing if the NX, which is supposed to have all of Nintendo's games and efforts backing it, is revealed with a relatively lackluster lineup. Nintendo knows that software is a big reason both the 3DS and Wii U failed, and the combination of their output was specifically designed to address that. Now with the NX reveal they need to actually PROVE that they've successfully addressed that.
What I see based on all the rumors (including those of LPVG) is a handheld device that can be disassembled to turn into a home console device. You put the screen portion into the dock, and you're left with two motion controller portions in either hand. It has essentially become a Wii when in docked mode. When undocked it is a standard touch screen handheld.