Via Insert Credit, I saw an interesting rumor that on the ESRB site, they have a rating for a GBA version of Samurai Shodown V. Unless this was an oversight, it's possible that they're bringing it out on the GBA.
http://ds-x2.com/index.php?id=4241
http://www.esrb.com/search_results.asp?key=Samurai&type=game&validateSearch=1
http://ds-x2.com/index.php?id=4241
http://www.esrb.com/search_results.asp?key=Samurai&type=game&validateSearch=1