Shares of Google Inc surged 14 percent on Friday, a day after blockbuster results and early signs of success in newer initiatives revived hopes that the Internet giant is getting back on the growth track.

The shares shot up to $600.25, climbing back to pre-2011 levels on Nasdaq. If the gain stands by the end of Friday, it would mark the biggest single-day gain for Google shares since October of 2008.

We are witnessing signs of increased competitive advantage for Google, particularly in Display and Local, with Search showing no signs of slowing, Evercore analyst Ken Sena said.

Sena raised his price target on the stock to $735 from $670, while Collins Stewart analyst Mayuresh Masurekar raised his price target to $725 from $680.

Jefferies raised its price target on the stock to $830 from $800, while Barclays Capital lifted its target to $730 and $675.

The results were strong despite a seasonally slow quarter, macro softness and substantially higher costs, analyst Masurekar said.

Going forward, the analysts expect Google to post strong revenue growth on international, display and mobile segments.

On a conference call, Chief Executive Larry Page said Google's new social networking service, Google+, had signed up more than 10 million people.

Clearly, the success of Google+ is a huge swing factor but the early signs of 10 million users and 1 billion items shared are encouraging, Wells Fargo analyst Jason Maynard said.

Evercore's Sena said he was encouraged by Google+ both in terms of traction and the company's plans to integrate its data signals and sharing capability into other products and services.

TOOTHBRUSH WORKS

CEO Page had compared Google's approach to being like a toothbrush, something you use twice a day.

We have made a good start but we are at only 1 per cent of what's possible... Google is just getting started... and that is why I am here -- working hard to lead this company to the next level, Page said.

The share jump that followed Google's results may be an indicator that the Wall Street is now more willing to give Page the benefit of doubt -- in terms of his investment and leadership strategy -- than just a quarter ago when he stunned investors by cutting short his appearance on the post-earnings conference call.

We think investors will welcome his reassuring comments about fiscal discipline and product focus, Maynard said.

The better-than-expected results and successful Google+ launch should stem some of the short-term stock angst about their investment and development strategy, Maynard said.

Investors had feared Google's ever-increasing spending would eat into margins. Operating expenses leapt 49 percent to $2.97 billion in the second quarter, to about a third of revenue.

Google is fighting technology heavyweights that include Apple Inc and Microsoft Corp, as well as upstarts such as Groupon, as it seeks to protect its lucrative search business at a time when mobile gadgets and social media are redefining the way consumers use the Web.

All five brokerages kept their top ratings on the stock, which was trading at $592.70 in late morning trade.

(Reporting by Supantha Mukherjee in Bangalore and Edwin Chan in San Francisco; Editing by Gopakumar Warrier, Roshni Menon)

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