http://www.nintendolife.com/news/2012/07/nintendo_determined_to_beat_hackers_with_wii_u_and_3dsI think the most recent update, which didn't really have any noticeable changes, was largely an anti-hack. I thought I'd pretty much heard they were having a lot of trouble making a flashcart for 3DS. But its not really something I follow. I thought in the past of getting a flashcart for my DS, but its not something I was seriously considering for 3DS, and that's probably just as well. I've never really been into modding and such though I've had friends who had.
Anyway, if you choose to go the dark path, beware!