I bought this the day it came out, returned it 3 days later. But don't take that the wrong way - I really did like the system. It was more buyer's remorse than anything (I didn't want to be cheated with a price cut or a system revision in the near future). A few thoughts:
I bought the black one. It really does feel like a dual screen PSP.
One thing I love about the system is the main system interface. Nintendo did a really good job with it. I look forward to seeing how they're handling the eShop in May.
I don't understand the complaints of DS BC. Maybe I'm crazy but I actually thought DS games looked better on the 3DS (then again, I never played in blow-up mode; I only played DS games with the SELECT trick. Also, I never upgraded from the original DS Phat; maybe my standards were just low). Slightly unrelated, but upon getting a 3DS I also got a DS game called Avalon Code, which is surprisingly really good. Now that I don't have a 3DS anymore there's no way I can play it though.
(broken DS)
3D slider is a vital inclusion. I usually play portable games on my side in bed; it's very difficult to see the 3D on max when I lay on my side. However I could see it perfectly when I put the slider on very low.
I didn't experience headaches, vomiting, or bleeding eyes with 3D, but it did make my eyes very tired. I liked playing around with the system right before going to sleep.
I've never owned a Wii, so I was new to Mii's. I've always despised the look of Mii's, but I actually had quite a bit of fun with the Mii Maker (another sign of my dark descent into casual gamerdom). The Mii photo taker thing wasn't very accurate for me. I hope Nintendo releases some kind of RPG maker one day with Mii integration.
Camera - seriously terrible. Grainy, low resolution, extremely sensitive to sudden movements. You'd think they used a phone camera from 2002. The contrast between the AR polygonal models and the poor quality of the camera is especially jarring.
Despite that, AR games was my personal favorite of the internal software (loved the music/sound). Never played Face Raiders.
Nintendo really needs to find some way to send data from an SD card over wifi (maybe with a system update?). I have very little access to computers that can read SD cards. I'd like to put music on the system in case any games ever use custom soundtracks.
Not sure what kind of "pop-out" effect Bebpo is talking about, because I actually did notice some pop-out 3D, even in the internal software (for example, the orbiting wrenches on the logo for "Settings" slightly popped out). However, I'm opposite of Bebpo in this respect: I actually prefer the "layered" effect of 3D as opposed to pop-out. That is, when the 3D makes it look like you're looking into a little box. I think that'll be really useful for certain games.
The analogue slider is the most pleasant surprise for me. The model I played at E3 2010 had a really terrible slider; it was wide, "slippery", and very hard to grip onto. The one on the current model is smaller and more "rubbery" so it has a much better grip. Massive improvement. Made some DS games actually play better.
The only major complaints I have of the system is the battery life (obviously) and the d-pad placement. Reaching for the d-pad under the slider was really awkward, especially for pressing down. Which is sad, since not all DS games (particularly top-down 2D games) are super friendly with the slider.
All in all I really enjoyed the system. I'll own it again someday I'm sure, but not anytime soon. I look forward to seeing Nintendo's/third parties' plans after E3.
