HipChat is used among by all members of our technology team. We have a series of private and public rooms dedicated to various projects. We've integrated our instance of HipChat with other Atlassian products such as Bamboo and JIRA in order to keep track of builds and code changes to our product lines.
While the many updates and improvements to HipChat are welcome and appreciated, sometimes it seems like they're rushed, and often times released prematurely. There have been at least a few occasions in which the enhancements that were released could have benefited from more QA.
HipChat pretty consistently takes a while to start up, particularly when recovering from sleep. It often takes at least one attempt to log in and having to "Try Again" before successfully being logged on.
More stability during remote use. When connected via wifi, some features don't work consistently (e.g. being able to load past conversations).
As previously mentioned, we leverage many of the HipChat bots, and integrate with Atlassian JIRA, Bamboo, and Confluence to monitor the status of code builds and for centralizing discussions about individual projects.