Android's browser does a good job at rendering complex web pages, but it doesn't have Flash support and it's really slow. You can zoom in, zoom out and move inside a web page. Here are some popular web sites rendered by an early version of Android's browser.
Useragent.org:
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Gmail:
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Google Maps:
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NY Times:
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Yahoo:
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Digg:
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YouTube video:
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Adobe:
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Acid2 Browser Test:
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Apple's iPhone site:
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iGoogle:
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