We're trying to implement a strategy for how we transition our builds from RC to released retail code.

When we label a build as a release candidate, we send it to QA for regression. If they approve it, that RC then becomes our released retail code.

I liked the idea of "obvious" labeling of versions so that a user knows whether they have a beta or an RC or retail code... where you would have some obvious watermark in non-retail code (think Windows 7 where the RC or non-genuine builds watermark in the bottom right).

... but it seemed strange to us to manipulate the project (to remove the watermark) once it passed regression. If QA certified version a.b.c.d then our retail code should be that same version, not a.b.c.d+1

what strategies have you employed to clearly label non-release software versions without incrementing your build to disable the watermarks in your retail code? One idea I've considered is writing your build to look for a signed file in the installer archive... non-release code wouldn't include this file and so the app would know to display a watermark.

But even this seems like QA is then working with non-release code.
Ideas?