Only reason why I am asking is because let's face it, these are the two biggest hyped games of 2014 that are going to be available for more than one system. I would think Destiny would sell more because it's simply available for more systems, but Smash might sell more because I would guess more people play the 3DS currently than the PS3 and XBOX 360 based on sales. Also the fact that Smash has sold more than 2.8 mill copies Worldwide AS OF 10/7/14 for just the 3DS is quite a feat itself, and it isn't even out for the Wii U yet (Full article here: http://www.ign.com/articles/2014/10/07/super-smash-bros-for-nintendo-3ds-sells-over-28-million-copies).
That's about 40% of Destiny's sales of 6.42 million sold worldwide for one system, and It hasn't even been out as long as it has (only in Japan). Needless to say, the threat of Smash passing Destiny with the help of the Wii U version on the horizon is there.
Will Smash sell more than Destiny in it's lifetime sales? Or will the massive DLC for Destiny give it enough legs to outrun Smash Bros, along with it being more available on more systems give it the edge?