I am Test Lead at THQ. Much of what Gold Roger said is very true, however, your job stability and ability to move up in the company varies greatly depending on the company.
At THQ they have a fairly stable testing position. They have gone away from the "hire tons of testers for summer then dump them after all the projects are finished" strategy. They are now staffing a large amount of testers all year and are hiring at multiple times of the year. So testers stay around longer and are able to make permanent much sooner. From there, permanent testers can move up to other positions such as First Party Specialists(specialized testers who make sure that all console games follow the rules set by Nintendo, Sony, or Microsoft), Test Leads, and Test Supervisors. Test Leads and Test Supervisors commonly move to Production within the company or be able to jump to Production or Design at other companies.
Being a QA tester can be a very good way to break into the industry, because it teaches you the work ethic required in the industry and it covers that very commonly seen requirement of "industry experience" on other positions.
Of course, you still need the skills it takes to get into the desired positions.
