Alright, I'm just going to give the final word on my own personal experience and opinion on the 3DS.
I brought the 3DS on day one because I enjoyed Nintendo DS and was excited to see what its direct successor had to offer, and I liked what was shown of it at E3 2010. I also like to support systems I'm interested from as early on as possible to help vote with my dollars in favor of more games coming out for it.
Some might call it "fanboyism", but I did this for the PSP as well, with the exact same intent. In fact I was there on launch day for PSP.
I was also interested in the 3D display on the 3DS. Some might say this is an invalid reason to be interested in the 3DS and that "I was suckered in by a gimnmick.", but if adding new features and technology to a system is somehow invalid or "cheating", then I must have been a huge idiot back when I literally had dreams over the Nintendo 64, Dreamcast, and eventually PS2 on the basis of graphical improvements, online gameplay, and force feedback, which earlier systems didn't have.
Just like earlier improvements employed to sell other systems, the autostereoscopic 3D display on the 3DS is simply an employment of new technology to gaming, which is what's defined every earlier breakthrough system, so why not this one as well? I don't at all remember anyone jumping down Sony's throat and pointing fingers of shame at them over their push for 3D gaming on PS3 that cost a minimal 500 dollars extra in addition to their 300 or so dollar console, but when Nintendo actually builds the 3D technology into their platform all of a sudden it became fashionable to disparage 3D and actually cite the 3D a as a reason the entire platform isn't worthwhile. It doesn't make sense to me.
Nintendo isn't obligating anybody playing the system to use the 3D. Some claim that the 3D feature is "worthless" on the basis that the 3D effect can be adjusted to be less intense, or turned off entirely. This is backwards logic because the 3D only works BECAUSE it's adjustable. Some games have more intense visuals than others, everyone's eyes perceive 3D images differently, while a few people can't see it at all.
In my experience, the 3D display works so brilliantly I almost forget its there. If you have two fully working eyes everything you see in real life is already 3D, so once you get used to it playing video games it's very natural, comfortable, and enjoyable. The sensation makes navigating polygonal environments and judging the distance between objects very easy, and while its not at all necessary to play any 3DS game, games that use it well either simply look nice, or leverage it to employ interesting concepts that otherwise wouldn't have the same impact.
3D in gaming is like visual force feedback, its fun, nonessential form of feedback that's totally not needed to play the game (most games let you turn it off), but its a welcome addition when used properly. There's a reason people were upset when the Sixaxis dropped support for it back in 06.
As for the game selection for 3DS, some my try to say that there's something wrong with me for saying this, but I've been more than pleased with it and have gotten hours of enjoyment out of the games available for this system.
I've gotten more than 20 hours of playtime out of Mario Kart 7 and will likely be playing this game for years to come. I've played every game in this series and the only ones I actually enjoyed were Mario Kart 64 and Mario Kart DS. I didn't like the graphics or controls of the GBA and SNES games, and Mario Kart Wii didn't look especially exciting to me at all, so I simply didn't buy it.
Kart 7 on the other hand, I rushed to buy mostly on the basis of its online and community functionality, which didn't disappoint me at all. The courses are well designed, the vehicle customization is fun, the graphics are vibrant, it's really everything I could want out of this game. I personally see no reason to dislike it unless you simply don't like cart racers.
As for Super Mario 3D Land, I'm more than 20 hours into that game as well, and it's still throwing plenty of surprises and clever ideas in my direction. Even if it looks like earlier Mario games and employes the same basic mechanics of running and jumping, (as it damn well aught to) it's still a breath of fresh air with excellently constructed, fun to play stages, and serves as a long awaited re-consideration of how a 3D Mario game can be constructed. It also has a great soundtrack.
And this coming from a guy who gave up on Super Mario Galaxy 2 perhaps halfway through because even though I knew it was a great game, it just didn't hold my interest and make me smile enough to actually get me to turn on my Wii to play it every day.
I've spent over forty hours on Virtual Console and 3D Classics games on the 3DS, some of which haven't been legitimately available for purchase since the early 90's. If the ability to play and download vintage games on the 360 or PS3 can be considered an asset to their overall featureset, I don't see why that shouldn't apply to the 3DS as well, especially since many of the classic games on 3DS are exclusive to any other platform.
Ocarina of Time 3D I have just over 10 hours on. Unlike most people who played the game from beginning to end tens of dozens of times since 1998, my only complete playthrough of the game was my very first one on N64, so the game is still very fresh to me. I just chose to stop playing since I'm up to the 3rd dungeon and games that take place inside living creatures gross me out and I need to find a day to just follow an online walkthrough and get it out the way already.
I've gotten close to 20 hours of enjoyment out of the StreetPass Mii Plaza and Swapnote combined, I've found Street Pass in general to be one of my favorite features of the system and hope that future systems, including home consoles, utilize versions of it in the future. Swapnote on the other hand has been a load of fun to use with my 3DS owning friends, though it suffers from the lack of an on-screen keyboard.
Short 3-6 minute gaps of the Nintendo puzzle game Pushmo have accounted for about 5 hours of gameplay over time. This has been my favorite puzzle game since Pokémon Puzzle League and makes excellent use of the 3D display.
I've also been playing Dillon's Rolling Western, which is sort of like a cross between an action game and a tower defense game, and is also from Nintendo. I've had fun with it so far, but it suffers from a lack of a quicksave feature, and the levels tend to take place 20 to 30 minutes at a time, so my opportunities to get into this game have been limited up to this point.
I recently got Kid Icarus uprising, and am only three hours in, most of which has been spent experimenting with the multitude of weapons and difficulty levels in the first two stages alone. This is another game I know I'm going to be playing for a while to come.
Other retail or downloadable games I look forward to playing that are already released and I simply don't have the time for yet, or have already been announced include:
Resident Evil Revelations, Rayman Origins, Fire Emblem, Ketzel's Corridors, Paper Mario, Mighty Switch Force, Rune Factory, the eShop Pokémon games that were recently announced, Luigi's Mansion 2, New Super Mario 2, Sonic Generations, Sakura Samurai, Mutant Mudds, and Mario Tennis Open.
And I know I'm unlikely to ever actually get ALL of those games, let alone what might be announced in the future.
So that's the long and short of my Nintendo 3DS experience and why I have enjoyed the system up to this point. Your personal mileage may vary, but having owned many systems by many companies since my first GameGear back in the early 90's, I can say that I've never enjoyed owning and playing an up and coming system as much as I have my 3DS.
