I think the biggest drawback to a two page resume is all the people who, for no real reason, seem to insist that a resume only be one page. If you've got something to say, say it. If you are just trying to fill space, save it.
I'm just out of college and i have a two page resume. This is because of education (BA Philosophy, MS Computer Science) and extensive work history. I had 4 different tech related jobs that are relevent to what I do now while in school (internships, volunteer dba for the cs department, stuff like that). But I also had a long and successful career in the hotel and restaurant industry and want to mention my management experience from that part of my life. So I list 6 jobs on my resume, the 4 related to CS, my last restaurant job (GM of a fine dining restaurant), and a single composite 'job' summarizing the 20 yrs i spent working hospitality.
And just today I had an interview for a job for which I do not have the technical qualifications, but they are interested in me because of my management experience. It's a management tracked position and they seem to believe I can learn the technical skills quicker than most people with the tech skills can learn management skills. I'll let you know if I get the job.
[edit]A great article on resume writing:
http://www.rockportinstitute.com/resumes.html [/edit]