@Benjamin Cook, this is a classic popularity is more important than software freedom argument, mixed with the have to use proprietary software argument.

The same arguments work to argue against all copyleft licenses: after all, some companies won't adopt GPLv3'd software because they fear giving users the freedoms it upholds.

Perhaps you believe that the freedom to proprietarize software is a fundamental right, just as I believe it's a fundamental wrong. If you do, then your arguments would make sense. But, I don't think that's what you believe, because it seems you bleieve that Firefox is somehow a "force for good" even while it incorporates proprietary software and DRM.

I don't know what good you're putting first there, except maybe popularity. I don't think popularity is that important.

As I said elsewhere in this thread, Mozilla could make a huge impact by setting up Firefox so that every time a DRM'd video was encountered, it could explain to the users why it doesn't work and explain the manipulation that the media companies have done.

This would make a real difference. Sure, many users would switch to a browser from some other for-profit company. But, may people switched from GNU/Linux to Macs, which was based on BSD. Should we have taken that as a sign that we should relicense Linux and GNU under non-copyleft in hopes that more people would use it?