I was torn about whether to post this here or over on the WP Engine blog. I chose here because we tend to post technical stuff here. Please DO NOT upgrade the W3 Total Cache plugin to the newly released version. It is incompatible with our current system and WILL BREAK YOUR BLOG. There are also known incompatibilities with some of our technology stack. We are working on a process to allow upgrades to this version and will be working with the developers of the plugin to achieve compatibility.
Until then… do not upgrade this plugin.
Additionally, as a customer, you do not need to worry about this plugin at all. We automatically configure optimal settings for your blog and administer it as part of our core service to you.
Thanks. We really appreciate it.