so who do think will be the next 3
Barring One Piece (which will probably outlast the next big 3), the 3 I see dominating shonen are Fairy Tail (ranked #4 out of all manga in sales in Japan in 2012), Magi (ranked #9 in sales and is a less than 4 year old series), and Toriko (ranked #11 in total sales and is just older than Magi). I don't count Hunter x Hunter because it is about as old as One Piece and thus older than 2 of the big 3. I don't think it can be counted especially with its very long hiatus spurts. I don't count Katekyo Hitman Reborn either because it was in the top 25 sales last year but abruptly ended due to funding. And D Gray Man is pulling Hunter x Hunter moves by releasing a chapter less than once every month, so it's popularity is not quite the same as it was. The last problem is that Fairy Tail is rumored to be ending around the same time as Bleach and that the next arc could be the final arc (the Mangaka is currently working on another manga), and this it wouldn't be around long enough to be part of the next big 3. In that case, probably Beelzebub could step in. It's a top 20 manga now and is the same age as Toriko/Magi.
I don't want to think about this.....
Although having said that Bleach is just going downhill for me massively, but Fairy Tail isn't a good enough replacement for it either. I just wish One Punch Man became a weekly manga with an actual storyline lol.