Google Talk (Grand Central)
Actually, that's Google Voice, not Google Talk.
In house, Google developed Google Wave and Google Buzz.
And Chrome V8, Gmail, Google+ (including Google+ video Hangouts), Google Wallet, Google Offers, Google News, Google Books, Google Music, Google Now, Google Keep, Google Art, Google Cloud Print, Google Image Search, Google Video Search, Google Music Search, Google App Engine, Google Compute Engine, Google Flights, Picasa, Google Translate, Google Knowledge Graph, Google Shopper, Google Currents, etc., etc., etc. (I got tired of copying entries from the Wikipedia page). And of course there's now all of the hardware -- various tablets and phones, Chromecast, Chromebooks, Google Glass, self-driving cars, and more. Oh, and Google Fiber. Plus a bunch of other Google X projects, most of which not even Google employees know anything about.
In addition, nearly all of the properties that began as acquisitions have been substantially, if not totally, rewritten to provide more features and to enable them to scale to massive volumes. For example, Google Maps was acquired when it was a standalone program written by two guys. It's unlikely that there is a single line of code remaining from that original app in the modern multi-platform, massively scaled system that incorporates many different data layers, including all of the StreetView imagery (another purely Google-originated endeavor).
Actually, even if Google had simply acquired everything, it would still take a lot of innovation to rearchitect it all so it can scale for a billion users. There's a lot of purely internal innovation that is required to make all of this stuff work, like Bigtable (and now Spanner), Borg, MapReduce (and now Flume), plus all of the libraries/dev tools -- including many which have been open sourced like Guava, protobuf, Gson, Gerrit, Keyczar, and many, many more.
"Google doesn't actually invent anything" is a popular /. meme, but it's completely untrue.
As for why this patent legislation matters to Google, Google has always hated the patent arms race; it costs software companies money and agility, and gives them basically nothing in return.
Google is a company of software engineers, right to the very top, and nearly all software engineers hate the ridiculousness of software patents, and the way patent trolls stifle extract cash from the people who are actually doing cool stuff to give it to worthless do-nothings. For a long time Google simply refused to play the patent game at all, until it got seriously burned. So then Google began lobbying hard for patent reform, spending millions per year, and this is just one piece of that large, multi-pronged effort. At the same time, Google realized that it had to get into the patent game itself to survive, and so purchased Motorola and some other large piles of patents, and began rewarding engineers for writing patents. But Google would really prefer to fix the system.
(Disclaimer: I'm a Google engineer.)