I'm not at E3 right now, and one thing that is killing me about not being able to go is missing out on all of those wonderful StreetPasses. I'm addicted to using StreetPass to complete my puzzles, and it's killing me I have three incomplete puzzles that I could easily fill in two days or less at E3. As a resident in the US, the only way I can really get anything meaningful out of StreetPass is by going to a gaming or anime convention where I can mingle with tons of people who own a 3DS as well. When I visited Japan a few years ago, I was able to StreetPass several people by simply walking to the train station. We don't have a population in the US that forces us to walk amongst different people every day to make StreetPassing viable. Nintendo is well aware of this, and they want to change that for the US and Europe.
Nintendo wants to create a framework of relay stations that will be online servers accessed through public Wi-Fi. With these stations, 3DSes can communicate with them and leave game data on a server instead of requiring to do the same with other devices. This will not only increase the chances of your data being received by another 3DS, but it also increases the chances that your data will be picked up by several devices instead of one.
I admit, as soon as this firmware update goes in place and the relay stations are set, I will carry my 3DS with me as much as I did when I first got it, just to hope for a StreetPass or two. These picture puzzles aren't going to complete themselves.