Also at risk are users of Adobe products including Acrobat Reader and Flash. And the security firm predicts Google's Chrome OS will "create another opportunity for malware writers to prey on users".
The company also anticipates smarter and more dangerous Trojans that "follow the money", as well as a "significant trend toward a more distributed and resilient botnet infrastructure that relies much more on peer-to-peer technologies".
In an interview, David Marcus, McAfee Labs' director of security research and communications, said he expects "an explosion of Facebook and other services targeted by cybercriminals". In addition to malware such as Koobface that spreads among Facebook users' friends list, Marcus expects an increase in rogue Facebook applications.
For more on this story, read "More attacks expected on Facebook, Twitter in 2010" on CNET News.