At the moment, the usage of StreetPass outside of Japan is a lot less and interesting than StreetPass usage inside of Japan. But as announced at E3 2013, Nintendo is planning to fix this problem in a software update.
Well, the StreetPass feature will be changed so you’re able to “exchange data with others by visiting the same location even at a different time”.
This is possible because certain locations (mostly Wi-Fi access points at Starbucks or McDonald’s) will be transformed into “relay stations” with this update. These relay stations save your data and pass it onto other people while also passing your data onto other people. In the end, more StreetPass fun is had by all.
The software update will be released later this year.