My opinions on the 3DS are mixxed. Firstly, I will proudly state that I purchased it immediately upon release. The 3D affect is truely stunning, though far from the reason I bought the system. I spent the first few days with it playing the various AR games, creating Miis, and blasting away the faces of those that I know. However, these features eventually grew tiresome, and I wished to try out the street pass feature. This, of course, was impossible, as the 3DS is not highly distributed throughout the world yet. I did not purchase any games at lauch for obvious reasons.
Firstly, I must say the 3D effect is stunning, and I see much potential for it in future games. The menu is easily navigated, and everything flows quite well. The Dpad is a nice addition that will satisfy many a gamer. The graphical capabilities are quite impressive, especially in games that have yet to be released. Overall, the 3DS is a great system.
However, the initial "failure" of the system is for multiple reasons. Firstly, in the several months since its announcement, I've only seen one commercial for it. This greatly limited its potential audience to those who happened to pass a demo, see a poster, or was already within the "Nintendo grapevine". Yes, many people have pointed out that it has higher sales than the Wii, but remember, when the Wii was initially released, they were nearly impossible to get, as each store was only given a limited amount to sell. Secondly, the Nintendo eShop and Internet Browser promised upon lauch was delayed, making anyone who didn't have a game find the system to be virtually useless. Lastly, and most importantly, its launch titles were quite simply "meh". There was no launch title that seemed to appeal, and many of them seemed no better than a DS game with 3D tacked on. The popular titles such as Zelda and Kid Icarus promised to us at E3 were absent- not being released until the summer or later.
Despite all this, I feel that, once these titles are released, 3DS sales will pick up.