Yay! Just what the world needs is another proprietary closed source chat system. Assuming its closed anyway, nothing yields source on Google, and the actual web site is down.
If its true, its likely it's only a small part of the score but who knows, it might be enough to push my domain into the good graces of gmails spam filters.
I doubt you'd get away with doing it for a domain sending legitimate mail, or at least not for very long.
> The author jumps to an unfounded conclusion which is pretty irritating and probably will make everybody who could help him not want to help him.
Apologies if you took it as a conclusion, it was only hand waving speculation, but google does have an incentive to make it difficult for the little guy...
> Gmail either rejects spam at SMTP DATA time, or delivers it to spam folders.
They do if you have DMARC enabled, and a REJECT policy, although they still seem to ignore it sometimes and I have no clue my mail is sitting in a spam box.
A lot of people rave about Slack, and I think it's very unfortunate its a very closed platform.
There's already http://www.mattermost.org/ a open source alternative, which I haven't tried.