Heise Security uses their crystal ball to make some predictions about 2007. Here's a snip:
2007 was the year of the super bots: Never before has malicious software been equipped with so many functions that help it to hide from antivirus software and to resist removal. The majority of malicious software programs used root kits, and their number doubled again on last years figure to over 500. Local privilege escalation vulnerabilities in Windows were increasingly exploited; accounts with restricted user rights were used to gain system rights. Initially, the protective functions in Windows Vista, which has been available for end customers since January, made it more difficult for malicious code to infiltrate the system..