Love the ability to take 3D photos, love the user interface, love the Augmented Reality game (included), and the Face Raiders sort-of-game (also included); both of these apps are short but they ooze Nintendo quirky goodness. Love that Ninty decided to include a 2GB SD card (though I've replaced it right away with a 16GB SDHC, in preparation for storing obscene amounts of 3D baby photos, and downloadable titles). Love the notion that I'll get rewarded for walking around with my 3DS in sleep mode; love the possibility of my 3DS meeting and playing other 3DS's without me knowing about it. Oh, and I love the charging cradle as well. Love the build quality.
Hate that there's only one game that interests me at this time, Steel Diver
,(UPDATE: NO WAIT, THERE ARE NO INTERESTING GAMES STILL; AND STEEL DIVER TURNED OUT TO BE A DUD) and it is rather overpriced; hate that even though I ran the system update, the 3ds store hasn't popped up yet, as promised - come on people, I've 16GB of SD HC card to fill up. (UPDATE: IT'S UP AND RUNNING, BUT SLIM PICKINGS AT THIS POINT.) Hate the battery life--I hope there will lately be a better one available, and that it will be user replaceable.
Nintendo! Did you forget you had this system? Oh well, I can still use it to take 3D pictures of my baby-girl.