TwitPic and some Twitter pages blocked behind Google's anti-malware curtain without explanation

Popular Twitter-based photo service TwitPic is currently being blocked by Google's malware checker. Upon trying to access TwitPic.com, the service's Twitter page, or any Twitter page containing a TwitPic, users are presented with a "Malware Ahead!" warning that urges them to turn back. The site is currently listed as "suspicious" by Google's Safe Browsing tool, even though it also states that suspicious content hasn't been found on the service in the past 90 days. TwitPic responded to the situat...