@Greg Spent over 10 years working in QA, and I've never used any specific tool for this purpose.
In my experience, it's nearly impossible to get test cases out of developers. We QAers had to stumble upon cases ourselves. In each case, we just stuffed our cases in as code via git or some other VCS tool.
Release management procedures either had us run our cases prior or concurrently with a release. (Yeah, scary, isn't it? :) )
@Greg From a QAing perspective, the best experience I've had was using the V-model of software development. Every half, we'd have a planning session and write up not only forth-coming requirements, but also test artifacts/requirements as well. These would be treated just like regular code requirements (e.g., tickets in a bug tracker, most typically).
Concurrent to mainline development, testers would write their QA tooling, and over time discrepancies resolved.
@Greg We'd then rely on regular continuous integration techniques for most things, but we'd manually run particularly expensive tests prior to release.
@Greg Is Testopia (a Bugzilla companion) still a thing?