I dunno, been buying other stuff while the 3DS library builds up. Was really close to getting it when RE Rev came out, that for me (combined with SM3DL and MK7) was the tipping point, that 3DS had graduated from launch-era to swing-of-things-era.
Anyways yeah, I'll probably get one soon, maybe even next week depending on how things go, although my older sister's birthday is coming up and I really want to go all out (for her and everyone in my family.)
I do keep forgetting 3DS is only $170 though, I walk around <insert 3DS-selling store here> and think, "Do I really wanna drop $250- oh, wait, it's not that price anymore."

Mario Kart 7 is the best Mario Kart ever IMO, so as a rabid Nintendo fan, yes you should!!
As long as it was MK DS with better graphics and better online that was always going to be the case! (MK Wii doesn't fit the criteria by virtue of the fact it's kinda different from MKDS, mostly being on a console.)