Upsource 3.0 has better support for GitHub projects, starting with a new "Connect to GitHub" screen. Another improvement is that when you're looking at a GitHub project using Upsource, pull requests become branch code reviews, and you can create and merge pull requests straight from the Branches page in Upsource.

One addiition to the software is the code analysis summary. This is part of Upsource's code insight features, and you can use it to see the difference between the new and previous versions of your code, along with any "issues" that were introduced or fixed in the changes you're looking at.

Another addition is the first of an automatic workflow generation in the form of automatic creation of reviews, along with assigning reviewers, if someone changes specific parts of the codebase. For example, if you know that some parts of the code shouldn't be changed, you can mark that section so that if anyone does make a change, an automatic review is generated. The developers of Upsource say that more workflow types will follow. 

Another useful addition is support for webhooks so you can notify external services, such as an issue tracker or a CI server about events that occur in an Upsource project. When an event occurs inside Upsource, a JSON payload is sent to the specified URLs using HTTP POST. 
Other improvements include better analytics so it's easier to group different types of reports, along with the addition of treemap visualization of project files. The IDE plugin has also been improved with real-time notifications in IDE, support for copying text from News Feed items and discussions, an improved News Feed UI, and links in comments.
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