Some users have a problem where images they have uploaded appear small on a white background, like this:

(Obviously with the pink area being white!).

This is caused by uploading an image that is smaller than 640 pixels. Our system "floats" images uploaded using the bulk upload tool onto a white background, so that if they are not square they won't get distorted. This doesn't cause a problem for images that are 640x640 pixels or larger, as they just get resized down to the correct size automatically. However images that are too small will appear like above. In some ways this is a good thing -- it tells you that it's too small (you can see the image will appear little by mousing over it in the list on the bulk upload tool -- you'll see the white space easier that way), or otherwise your images would appear like this:

Where they will appear pixelated and/or stretched. So make sure your images are nice and large (but don't go overboard -- a 21 megapixel photo isn't much use) when you upload them, so that we can be sure to post something that looks great to your followers.