Nodesummit.com is hacked, not Google. Redirect is active for referrer:
curl --head --referer 'http://www.google.com/url?{...cut...}' http://nodesummit.com
HTTP/1.1 302 Moved Temporarily
Date: Sat, 11 Feb 2012 00:32:36 GMT
Server: Apache/2.2.9
X-Powered-By: PHP/5.2.17
Location: http://costabrava.bee.pl/
Vary: User-Agent,Accept-Encoding
Content-Type: text/html