We hear more and more about malicious coding groups getting together to make their code specifically target certain companies or certain suites of software. Microsoft Office is one to note, which had people go so far as to generate an exploit that would only affect a certain company because of the way they transferred their files. On the other hand, a recent report from Symantec is claiming that the majority of malicious code writers are turning their attention to the home user. Of course, as businesses become more aware of outside threats and react against it, it makes sense for worm authors to turn in that direction:

"They're now starting to target home users quite heavily, primarily because home users are the weakest link in the security chain," says Turner.
Easier targets. Perhaps increased trust, as well, as web technologies become more prevalent than ever. People trust online resources more, and could become more susceptible. Not to mention the heavy reliance on email on IM, both of which are “trusted” access portals that could let just about anything slip through a firewall or A/V suite undetected, should someone get hit soon enough. Are the days of the mass-spreading worm over, with the focus being shifted to small groups?