Here we go again. The Internet giants are falling back in love with finance. After several years during which the big Internet players were content to let Yahoo! ( YHOO) be the go-to site for stock market data, Google ( GOOG) and Amazon.com ( AMZN) this week showed they are interested in adding to their revenue by sticking their toes in the financial sector. First, Amazon launched its financial services shop, announcing it signed up Fidelity Investments as the store's "featured partner" -- as Nordstrom ( JWN), Wine.com and Dean & Deluca are in other categories. For now, Fidelity is the site's only financial-services partner, and what little content is there, including a so-called blog, reads like ad copy for the fund family. Amazon's move could signal either a disturbing trend -- the retailer rents out chunks of its respected domain as ad space for other companies -- or a welcome one: Opening up its generally affluent, educated and tech-smart customer base to a variety of financial services while allowing them to compare information on fees, funds and customer satisfaction. Then, on Tuesday, Google took the wraps off of Google Finance, a site offering news and data primarily related to the stock market. Initial reviews of the site were mixed and cautious, if not critical. "Thumbs down for Google Finance," read the lead on Marketwatch.com. Self-appointed market pundit Henry Blodget, who made a lucrative career out of being wrong about the Internet, proclaimed "the beta landing page couldn't be less revolutionary." As anyone with Internet access knows, Google has made some notable missteps of late, just in time for a public-image backlash. So, the safe move here would be to instinctively kick Google's entry into financial content. Don't trouble your brain, just let your knee-jerk do the thinking for you. The big criticism seems to be that Google's new site isn't very new. To say that Google Finance looks an awful like the entries in this race -- Yahoo! and Microsoft ( MSFT) in particular, as well as dozens of smaller sites, including TheStreet.com -- is to miss what is truly ingenious about it.