I too am having the issue where My page validates fine showing the image I describe in my Meta tag. But when I click the button on the page. The tweet does not display the image nor does it tweet it if I post the tweet.
Here is my test page:
I have been struggling with this for a few days now and would buy someone a cup of special coffee 
if they can help me out! I have checked the troubleshooting guide a few times… I don’t see a problem…
Thanks…
**EDIT
I see the image next to the tweet HERE ABOVE when I embed the URL in this post… ODD… but I do NOT see it nor do my coworkers when we click the link on the page itself…
