MediaWiki 1.19/Post-deploy retrospective

We deployed MediaWiki 1.19 in February 2012. In the interests of doing better next time, please help us brainstorm what went right and what we need to look at. RobLa will then summarize that discussion.

Note: this is specifically about the MediaWiki 1.19 deployment, rather than the 1.19.0 release.

There are two sections: "What went well?" and "What do we need to look at?" For now, limit input to small (<140 character) bullet items. If you want to elaborate or respond, please take it to the Talk page.

What went well?

 * Pre-deploy testing of Commons gadgets on http://labs.wikimedia.beta.wmflabs.org/
 * Gross errors detected quickly, rollbacks were effective and fast.

What do we need to look at?

 * Swift?
 * Release notes were unorganized, hard to interpret, possibly inaccurate