Shares of Baidu (Nasdaq: BIDU) hit an all-time high today, after Pacific Crest analyst Steve Weinstein bumped his price target dramatically higher.

Maintaining his "outperform" rating on China's leading search engine, Weinstein is now targeting a price of $140. He was previously perched at the $80 mark.

Jacking up a target by 75% isn't for the timid. Weinstein's move also comes at a time when some of his rivals have gone the other way. Deutsche Bank analyst Alan Hellawell downgraded the shares last month. Unfortunately for Hellawell's bragging rights, the stock has gone on to appreciate by 19% -- and that's before this morning's pop.

Sure, it's just rotten luck for Hellawell to have downgraded a high-beta stock before tech stocks rallied through September. However, there are other factors bubbling up Baidu's ascent.

A new app platform is giving investors a good reason to raise the ceiling of Baidu's potential. Weinsten singles out Phoenix Next, which is Baidu's recent remake of its keyword bidding system for advertisers. It's ripped right from the pages of Google's (Nasdaq: GOOG) playbook, but everyone copies what works in tech.

So what about Baidu's shares? If they were "priced for perfection" when Hellawell downgraded the stock, valuations must be ridiculous these days, right?

Well, the upward revisions continue at Baidu. For his part, Weinstein now sees earnings clocking in at $2.29 a share next year -- with 50% growth come 2012. He was previously settling for net income of $2.02 a share.

Based on Friday's close, Weinstein's new target values the dot-com speedster at 43 times next year's earnings. It's a high multiple. Stateside search leaders Google, Yahoo! (Nasdaq: YHOO), and Microsoft (Nasdaq: MSFT) fetch bottom-line multiples of 17, 19, and 9, respectively, based on fiscal 2011 estimates. And that's without explaining that Yahoo!'s multiple is inflated because the market cap is backed by its valuable Asian investments.

However, you can't ignore growth. The $2.29 a share that Weinstein is modeling for Baidu's bottom line next year is a 62% boost from what the pros expect this year. In other words, Baidu is growing faster than its forward earnings multiple.

Sure, there are cheaper dot-com plays in China. Sohu.com (Nasdaq: SOHU) runs the much smaller Sogou search engine in China, and it can be had for just 14 times next year's projected profitability. New-media pioneer SINA (Nasdaq: SINA) trades for 26 times what Wall Street believes it will earn come 2011.

However, Baidu's runaway market leadership in China's juicy search space -- and a history of humbling the naysayers -- make it hard to bet against the company.

Weinstein has the right idea.

Do you think Baidu is a good buy at this point -- or is too late? Share your thoughts in the comments box below.