If you have an existing license to Upsource 1.0, then 2.0 would be a free upgrade for you. If you don't have an existing license, note that a 10-user plan is free anyway.
The new Upsource release comes with numerous improvements across many areas including code review process, support for version control systems, and managing reviews from within the IDE. Here are some of the highlights of the release:
Upsource 2.0 delivers an IDE plug-in for code review that works with IntelliJ IDEA, WebStorm, Android Studio and more IDEs built on the IntelliJ platform. The plug-in helps submit revisions for review and manage the code review cycle, shows review comments and allows creating new comments right from within the text editor.
Upsource 2.0 adds support for SVN branches along with Git and Mercurial branches. Other improvements in terms of VCS include support for Git and Mercurial tags, as well as setting up multiple VCS repositories in a single Upsource project.
If your team is into Java development, you should know that Upsource 2.0 brings Java code inspections, navigation and search to Gradle-based projects in addition to Maven that was supported earlier. Upsource 2.0 can also compare Java code usages across revisions with a new action called View usages diff.
Upsource 2.0 streamlines managing code reviews and taking part in them. For example, reviewer suggestions help authors find and assign appropriate reviewers faster. For reviewers, Upsource provides a new control that helps show or hide revisions in a review: when new revisions are added to the review, a reviewer only sees the diff of those new revisions without having to re-read previously changed code.
Collapsing unchanged fragments and opening the side-by-side diff in a full-screen popup help drastically decrease the amount of code that a user has to look through when inspecting changes between any two revisions.
Multiple improvements to the commenting system include live comment preview, persisting comment drafts, and adding inline comments to the Review timeline for a quicker overview of things to be improved within a review.