I have just updated to latest W3TC, and I ended up with tons of errors:
Fatal error: Call to a member function get() on a non-object in /var/.../wp-content/object-cache.php on line 62
And I don't even use object cache.
Also, I ended up with broken several areas of the site that don't even load. I am using bbPress 1.0 plugin integrated in WordPress, and that one stopped loading as soon as I updated to new W3TC. I had to revert to old W3TC version.