No, not yet, but it may come out on a new system like when the first one came out for Nintendo 64 and how the 2nd and 3rd Super Smash Bros. came out on the Gamecube and Wii. Guessing from that SSBB2 might come out in 2011 if there's a New Nintendo System.
the maker has been Q&A about it and he said he will only make another one if theres somthing new to it he dosent just want to fatten it up with characters and rosters so there might be :)