How are you inserting the embed code?
The code on your page is this:
<iframe src="http://vk.com/video_ext.php?oid=-53823348&id=168360865&hash=4ed3800f6bea4446&hd=1" width="607" height="360" frameborder="0"></iframe>
but if I right click the video itself and choose “copy video code” it gives me this:
<iframe src="http://vk.com/video_ext.php?oid=-53823348&id=168360865&hash=4ed3800f6bea4446&hd=1" width="607" height="360" frameborder="0"></iframe>
For some reason the “&” symbols are getting encoded as “&”. If you try the second embed code it should work.
i dunno why, but after update VK thumbnails stopped working.
it’s working fine on test page, but in post preview i see nothing.
http://4.firepic.org/4/images/2014-04/08/omd4rl596lkx.png
http://4.firepic.org/4/images/2014-04/08/f16nqzeizerz.png
Discovered the issue and have a fix on the way.
Details for anyone interested: The tests were passing (despite not working in posts) because “the_content” filter wasn’t being applied to the markup during tests, and for some reason when it gets applied to the VK embed code it encodes ampersands as &.
Version 2.7.4 is out, let me know if it fixes the problem.