Using an SD card as additional storage on a MacBook Air

I recently put an order in for a stock 13" 128 Gb MacBook Air, the only upgrade I did was move to 8 Gb or RAM.

I've never been one to use a lot of space on my older computers, so I thought I would take a chance with the 128 Gb model. I know the 13" Air comes with an SD card slot, and I was eyeing the following 32 Gb SD card for additional storage:

http://www.amazon.com/SanDisk-Extreme-Class-Memory-SDSDX-032G-X46/dp/B004Q3C98S/ref=pd_cp_e_1

I'm new to Mac's, so I'm not sure how everything works. That said, I have a few questions for some of the more experienced Mac users.

I take all my pictures and videos primarily on my iPhone. When I connect my iPhone to a current Mac, it automatically pulls up iPhoto and asks me if I want to pull in all my newly taken photo's and videos, which is great. I assume this process pulls the photo's and video's onto the main hard drive. My son also likes to make goofy videos with me on Photo Booth, which I again pull over to iPhoto.

Once everything has been pulled over to iPhoto, is there a way for me to pull all the actual photo and video files over to an SD card, and still get iPhoto to recognize them (thumbnails, etc) when I open up the program?

If I'm able to move all my photo's and media over to an SD card and retain the same program functionality with them, I'm confident the stock 128 Gb SSD drive on my computer will be more than enough space for me to run all the programs (which aren't all that many at this point) I want.

I suppose I could get a USB3 thumb drive to do the same, but I rather like the idea of using the SD card slot. I know both the SD card and a USB thumb drive would "stick out" when used, but the SD card would a lot less so IMHO. Call me crazy, but that appeals to me me more. Are there any other advantages (other than higher transfer speeds) to using a USB thumb drive instead of an SD card?

Does anyone have any thoughts and or experience with this that they could share with me?