Very well presented talk about the things to consider when upgrading, rather than only enumerating what is new in the named versions.
I've seen "what's new?" presentations for both 5.4 and 5.5 before, but they weren't as practical as this one!
Great talk, well presented, and a really interesting discussion about alternative afterwards.
Very engaging.
Very practical talk about the use of Vagrant and Chef. Very engaging and only practical examples. Excellent!