Today I've noticed that when I get a new page of just-posted PAD images (either by clicking First or Next) I will sometimes get a thumbnail that comes in at a large size (vertical, horizontal, or both) instead of the standard size. This at least temporarily blows the uniform table cell size and really gorps the page. Eventually it usually settles back down to the correct size.
This might be due to either of two non-standard configurations I'm operating under today. First, I've had to revert to my dial-up line until my broadband connection gets fixed. Maybe this always happens, it just is so fast with the broadband that it isn't noticeable. Secon, I'm using Firefox now as my browser (which, actually, isn't "non-standard", since I'm not using it exclusively -- almost). Don't know if it might handle the image sizing differently.
I haven't done any real testing, but I've only notice the problem on the PAD recent uploads page.