The issue isn't them releasing an FOSS version, it's that they release it at all. The only google application so far that has been satisfactorily ported to Linux is Google Earth. And yeah, that was released as a proprietary app in binary form.
I'd like to see their apps ported too, but I don't really care whether they're open source. I prefer that, of course, and that would be better for them as it would result in a better end product, but like you, I'll take a proprietary app over nothing at all.
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