From reading the manga (up to the most recently published volume in America, 17), it's really standard Shonen done well. It has all of the standard tropes, but it's really over the top. It really is a modern Fist of the North Star, but even sillier than that.
Speaking of FotNS, my first exposure to the series was the OVA that was in the Jump Super Anime Tour awhile back. The style and animation of that thing were amazing! Unfortunately, the current anime has neither. They're really pandering for young kids more than many Shonen that I've seen in a long time. Because of that there's a ton of filler and unnecessary side content that's really boring. I've been watching the anime slowly, but I may just give up all together soon. At least One Piece has some really great drama and voice acting to go with its boring anime. Toriko has neither on that front as well.
I think that's why it hasn't taken off. It's just too by the numbers and offers nothing new or interesting. It has the action of DBZ. It has the manly musculature of Fist of the North Star. It has the world creativity of One Piece. What's new?
The only thing more derivative is Fairy Tail.