A recent change to Twitpic has made it so that images larger than 600px in width are automatically downsized.
post #992551 -> http://twitpic.com/6ie9zx/full From 1074x1624 to 600x907
post #1281257 -> http://twitpic.com/awmgxp/full From 3744x5048 to 600x808
And then there's this confirmation from Twitpic's support: https://twitter.com/Cabel/status/279419147849453568/photo/1/large
I'm worried this change might cause downsized duplicates to be uploaded, so I'm posting here to try to get the word out in hopes to limit this from happening as much as possible.
Updated by DakuTree