The resizing of images for thumbnails generally works great, but for some reason it does not for a small subset of images. This subset seems to be GIF images with large transparent backgrounds, e.g. logos. When they are being resized, some of the foreground is being dropped. This dropping does not occur if you resize in Photoshop. Could it be that a simple change in setting is needed?
It is not a deficiency of GIFs in this case. That is, it can be resized correctly. I did the following one in Photoshop (still transparent): http://en.wikipedia.org/wiki/Image:Techcrunch-transparent-photshop.gif