UPDATE: The iframe has once again been removed, and GMC admin Chronic claims that “as far as he knows, YYG has applied the patch”.
…As of 9. September, 2008, 19:15 GMT, an malicious third-party iframe has once again been embedded on the Game Maker Community (visit at your own risk).
The iframe appears to exist only on the GMC homepage and not on individual forum/topic pages.
There will be no more GMC malware related posts on GMB.