This will heat up the closed vs open cannard argument again I’m sure. Google has pulled 21 apps from its Android Marketplace, all by the same developer Myournet because they contain malware. According to reports the Apps were essentially pirated versions of existing Apps that Myournet inserted a trojan into and then re-purposed the App. The Apps were also popular downloads, netting by some accounts over 50,000 downloads.
The trojan gets root access to the device, captures data, and then downloads other software to create more mischief. Google was notified by the blog Android Police about the issue and acted quickly to remove the Apps.
You can find a complete list of the malicious Apps here.