About what we saw here: http://sitecheck.sucuri.net/scanner/ / http://labs.sucuri.net/db/malware/malware-entry-mwjs2368
Let us inspect this piece of code: http://jsunpack.jeek.org/?report=52ced770f769ce5160927c25faa4e8ece3b66861
(view this in a sand-boxed browser with NoScript and RequestPoicy extensions active)
and to understand the mass infection proble, read: http://blog.sucuri.net/2011/08/mass-infection-of-wordpress-sites-counter-wordpress-com.html
link article author = David Dede. Know that this form of Malware Dunp has been around sincve 2011.
We came across a similar issue earlier here: http://forum.avast.com/index.php?topic=107715.5;wap2

And here we see the hex-decoding: http://ddecode.com/hexdecoder/?results=5d031ad7b2822f26b88b830110745e61

polonus