Update: The feature, dubbed touch to search, is live as of Chrome 38.
Google sometimes gives us a hint of what it's working on if you're willing to dig for it. Buried in the new Chrome Beta for Android update is something called contextual search. It's not completely functional right now, but you can take a peek at some aspects of it.
To enable contextual search in Chrome Beta, go to chrome://flags/#contextual-search in the address bar. Tap enable to activate this feature, then restart the browser using the button that pops up. Once this is done, you'll be able to tap any word on a page to get an interesting little search UI at the bottom of the page. It shows the word you selected along with the words around it. Trying to launch a search by pressing the Google logo brings you to an inaccessible internal Google page on the layers.sandbox.google domain.
Even though we can't see the results right now, it's likely this feature is going to perform some sort of targeted search that looks for the chosen word in a context similar to the one you selected. It's not very useful right now, but interesting to see what Google's up to behind the scenes.