On the GitLab blog it was stated that Gitorious wasn't profitable anymore.
Rolf Bjaanes, Gitorious CEO, gives some background on the reasons for the acquisition: “At Gitorious we saw more and more organizations adopting GitLab. Due to decreased income from on-premises customers, running the free Gitorious.org was no longer sustainable. GitLab was solving the same problem that we were, but was solving it better.”
“This acquisition will accelerate the growth of GitLab. With more than 100,000 organizations using it, it is already the most used on-premise solution for Git repository management, and bringing Gitorious into the fold will significantly increase that footprint.” says Sytse Sijbrandij, GitLab CEO.
Starting today, Gitorious.org users can import their existing projects into GitLab.com by clicking the “Import projects from Gitorious.org” link when creating a new project. Gitorious.org will stay online until the end of May 2015 to give people time to migrate their repositories. Existing users of Gitorious on-premises can contact sales@gitlab.com for more information.
GitLab can be hosted on-premises using their free and open source Community Edition.