Stuart Feldman of IBM research has some thoughts on the issue of testing and quality assurance.  He contends that QA is a process whereas testing tends to be technology-based and an afterthought.  He describes the difference here: 

"What goes into QA? Testing, of course, is a key activity. There is, however, an adage that “you can’t test quality into a product.” A solid test plan should catch errors and give a measure of quality. A good QA plan ensures that the design is appropriate, the implementation is careful, and the product meets all requirements before release. An excellent QA plan in an advanced organization includes analysis of defects and continuous improvement. "

I think what we call what testers do is largely semantic but agree with Stuart on what this activity should be.  If testing is merely about finding bugs, it is insufficient.  It needs to be about assessing the quality of the product as a whole. 

Stuart also spends some time detailing the different levels of testing required for various levels of products.  This ties in well with the software engineering discussion we're having elsewhere on this blog.

hat tip to /.