Capcom's Christian Svensson was recently quizzed on whether there would be a version of Super Street Fighter IV for the 3DS eStore.
C3 member Linkyshinks recently quizzed the Capcom Unit Team on whether there would be a downloadable version of the game - the short answer, no - and as for any other eStore content, Capcom are currently working on understanding the system and how it works to produce content different from retail releases.
We're still getting up to speed on the estore programs and parameters. My current understanding is that anything available on the eStore will in some way shape or form have to be a different game than what's offered at retail according to NOA's communications with us.So to answer that question, we have no plans at this time to make a "different" version of SSFIV for the eStore so for the foreseeable future, retail is the only place it will be.