That being said, the example ad shown in the article ("Slack is so last year. Now it's Ryver") just made me angry. Anyone who has been in tech a while has experienced this neurotic, senseless need to switch tooling every year because some middle manager decided to.
Like what Gett is doing: "We pay more than Uber!"
I think that's a pretty strong approach.
I suspect that said "neurotic, senseless need" to keep up with the corporate Joneses is what drove many organizations to adopt Slack in the first place. That leaves them feeling vulnerable about the next thing that might be coming up, which they don't want to miss out on. IMO Ryver is being rather clever by playing on that insecurity so openly.
The only killer feature I would have any interest in would be syndication across various communication tools.