I just got my pearl... and the micro SD card will simply not fit all the way in like it is supposed to. I have it the right way, but its just not going all the way.
Try using something flat like a small flathead screwdriver to help gently push it in. If that doesn't work check to make sure nothing's blocking the slot. And I know you said you have it facing the right way, but double check just to be sure.
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It will stop and not go in any farther if you have it upside down, but if you're sure you have it the right way up (contacts up if you're looking at the screen) then I'm not sure what might be wrong.
but i wanted to let you know what happened! I actually got it in there! The spring that clicks in was broken, and i pretty much forced it realllllly hard into the slot. When I saw "media card detected" I flipped!