I would never say Github is superior to Bitbucket. I haven't checked if they have changed the rules, but on the startup I was working on, Bitbucket provided superior value by far. They allowed free private repos for teams of up to 5 users. After 6 months we ended up paying for the basic plan to accomodate about 10 users.
I am mostly used to command line Git during my daily routine, but the designer/manager was happily using Sourcetree. But as far as some products that are kind of worthless, yeah Hipchat would be one. You are way better off using Slack or even WeChat mobile/desktop app (if you are in China)
Until recently I would've said there wasn't at all much difference between Github and Bitbucket (aside from Github being the de facto home for open source).
However, I'd now argue that Github is significantly better value than Bitbucket for projects, rather than code. By that I mean, Bitbucket is just a component in the greater Atlasssian ecosystem, so it's not a huge priority to add and improve upon project management tools, as you're encouraged to use JIRA, Confluence etc. Even simple things like Bitbucket's Markdown README's not supporting HTML (in particular anchors for same page links) makes the project organisation experience a whole lot less polished.
Where Github shine these days is that they offer a pretty cohesive experience for an entire project's management. Code reviews have come a long way, as have issues and pull requests in general. More recently they've added support for Projects, which for the most part is a Trello clone with built-in integration into Github's issue tracker. Free hosting of Jekyll websites, previews and diffs for all sorts of non-text file formats etc. really put Github in front. Combine this all with the recent change to bill per user rather than per repo (which provides huge savings for small teams) and I don't at all see how Bitbucket are supposed to compete.
I still use Trello for management of clients' projects simply because my clients don't care about the code. However, I can definitely see myself transitioning entirely to Github Projects and the Github issue tracker in the near future.
Frankly, Trello did really well out of this deal from Atlassian. I know Trello have a lot of users, but I'm a bit doubtful about their ability to generate significant funds (paid stickers...?) With Github Projects maturing Trello were likely to lose a lot of users from the tech industry. Atlassian and Trello actually seem like a perfect fit, so it's a saving grace for Trello who couldn't have timed the acquisition better.
> the UX of Github makes it worth the extra expense.
Github UX is weird. It looks nice, and there's lots of nice functionality. But it often takes lots of rummaging to find the things I need, unless I do them every week. Bitbucket and Gitlab seem to be laid out better. Github is the only site I use regularly where I need to refer to notes.
I am mostly used to command line Git during my daily routine, but the designer/manager was happily using Sourcetree. But as far as some products that are kind of worthless, yeah Hipchat would be one. You are way better off using Slack or even WeChat mobile/desktop app (if you are in China)