Swedish meatballs are explicitly designed for low-quality meat, which is diluted by starches like bread and potatoes and flavoring. I think horse is delicious though, so that's probably why I remember those meatballs were so good when I lived in Sweden. Also in the brief time I worked at a student restaurant in Uppsala, Sweden, we served questionable cheap pub burgers (dressed often with salad dressing or mayo lol) that my co-workers told me were mostly horse or donkey. At the time I thought they were joking, but now I'm not so sure. I do have very fond memories of how good they were, particularly the lyxburgare of the Norrland's student pub, which was an abomination of garlic dressing, a fried egg, and meat, but have been unable to re-create them to my satisfaction here. I have had horse several times since (Gastronauts in NYC and Joe Beef in Montreal) and it really is delicious, as it has a sweetness lacking in other meats, so it could have been the horse meat. Of course these days I like to know where my meat comes from so I don't know if I could still enjoy those questionable Swedish pub burgers and meatballs. I was always impressed by Europe's food regulations, but apparently they are not enforced very strictly. I guess whether this stuff ends up in the US will come down to how good USDA's inspection service is. It will be interesting to see what happens.