Twitter constantly make some cards for my blog with delays. And sometimes it takes wrong images (although meta tags are fine and I asure you I haven’t edited them afterwards).
Here is one:
The image that should be: http://lh4.googleusercontent.com/-qWQo5wY2W3k/UgnlKs1ofXI/AAAAAAAAcpw/h_1qdBVnQ3A/s1024/red_bull_team_fan_hun13.jpg
While I was writing it the Card was fixed to the correct image (anyway it took aprox 2 hours to got it right).
And here is a few tweets which are missing Cards at all from the very beginning:
You can find more here: https://twitter.com/f1dbru (every Twit with a link should have a Card there).