1. No markdown support and half-assed code highlighting support. 2. No (real) message editing. 3. Silly parenthesis based emoji.
Its search is better than Slack’s; its performance is better than Slack’s; its integrations are better than Slack’s; its client memory and CPU usage are better than Slack’s (whether in a tab or as a real, native app); its group video chat is better than Slack’s (does Slack even have video chat integrated, with screen sharing?). Most importantly for us, its price was 4x better than Slack’s all while offering better features, performance, etc. The only thing it didn’t win out on was hype. (It should also be noted that HipChat could also be bought in a self-hosted configuration, which allowed for HIPAA compliance, something that Slack won’t even bother competing on. I didn’t need it, but hey, it matters to some people.)
Slack is an overpriced distraction monkey. They’re selling it like it’s the whole enchilada, but it’s a damned feature bullet. I personally cannot wait until Slack is dead, because it’s the worst chat service I’ve ever used (and I love full-featured integrations).
Now, I have to find a replacement for HipChat that won’t cost us US$200 per month for our office (if we pay a year in advance, more if we don’t).