I've seen a number of people asking why the cached page link has disappeared from Google search results.
Don't worry, it's not gone, it's just been moved.
Cached Link in Instant Preview
The cached and similar links are now in the instant preview which is activated when you mouse over a result and then hover over the double arrow.
My guess is that these links are not widely used, so moving them to the instant preview retains the functionality but removes some weight from search results. That's important given all of the rich snippets, site links, social annotations and authorship being packed into search results.
In all, I like the change. However, the fact that so many can't seem to find the link does make me wonder about the instant preview feature and whether the interaction is truly intuitive.