What do you like best?
HipChat is simpler and quieter than its main competitor, Slack. For JIRA, Bitbucket, Atlassian-suite users it's also far easier to integrate notifications for deploy and code review requests into.
It seems like a mix of automated notices and p2p messages keeps teams engaged with team activities and lowers some engineer's tendency for "are they really working on work" judgements. As a result, it seems like HipChat has helped some team members I've worked with to be a little less-critical of others. This is a huge boost for team dynamics and keeping everyone working in a positive direction.
Nonetheless, it's a low-friction way for teams to answer each other's questions with less interruption than a scheduled meeting might warrant.
What do you dislike?
Team chat is increasingly used by open source projects, conferences, and local meetup groups. Which also means many developers and engineers are pulled away from work topics to marginally- or non-work-related rooms they're already members of. Not that phones & social media aren't there already, but team chat does require some active management time to make sure everyone is using good judgement on how much time they spend there.
Also, beware adding non-technical employees to every chat channel. Some product managers and analysts can become distracting. HipChat can end up looking like an excuse for these roles to interrupt devs away from in-context code questions to out-of-context feasibility and spec questions.
HipChat also has some technical-speed issues on Atlassian's end:
(1) It tends to lag on client updates. Mobile client don't always seem to be updated on the same cycle as the desktop app. And the desktop app doesn't always match the web client's functionality. Chat still works, but if you're a HipChat power-team with labeling conventions and busy notice channels, this can make those hard to use well across devices.
(2) One of the biggest reasons to upgrade to the paid version of HipChat is the infinite search history. Ideally, this would replace team wikis and docs, because every standard & decision could just be looked-up when needed. Unfortunately the search system Atlassian has built has poor matching algorithms, and indexing seems to lag so badly at times that you can't look up recent chats at all.
Recommendations to others considering the product
Work with the team to set some team standards around what HipChat is acceptable for & discuss its goals. Aim to keep things work-related without crushing individuality & all fun (like gif-sharing). It won't stay 100% work-related all the time, but it's better than having team members off on Reddit or feeling like they want to leave for lunch early just to email something funny around. Plan to have the team's engineering manager do a few reminders about this a year, especially after new-hires.
Don't let "it's on HipChat" be the sole reason for going a full week without meetings. Don't expect the whole team to have read every HipChat message. HipChat isn't an effective summarization tool. Individuals need to do that when they prep for & run a meeting. The *whole* team or squad should be at a meeting.
Beware of adding non-technical users to every HipChat channel, especially ones where dev squads get technical. Be VERY WARY of adding the whole company to HipChat. It's not a replacement for all meetings.
What business problems are you solving with the product? What benefits have you realized?
HipChat helps team engagement with devops events, code reviews, and each other's progress. It's a low-friction way for teams to answer each other's questions and reduce total meeting time.
With off-site or on-travel team members the video chat system is a boon to productivity. HipChat makes it easy for devs to chat about specific topics as-needed, instead of scheduling conference calls and putting things off until someone is back in the office.