Which is Silicon Valley's most valuable tech firm -- Google or Cisco? Depending on when you check, the answer may vary. Hey, our lives are busy. Who among us has the time or the wherewithal to sit around staring at Google Finance and comparing the market capitalization of different tech firms? Fortunately, though, we’ve got the folks over at venturebeat.com to do that for us. And, lo and behold, they noticed something very interesting: Google — for a while anyway — ascended the mount to become Silicon Valley’s most valuable company, knocking router giant Cisco off its long held perch, with a market cap of $159.76 billion compared to Cisco’s $159.73 billion. Alas,the folks in Mountain View didn’t have long to savor their victory, with Cisco trading up today, around 2.4 percent, and Google up only around 1 percent, Cisco is again on top. Still, the folks over at Venturebeat say that GOOG’s got the MO (it’s stock is up around 10 percent YTD, whereas Cisco’s is trading down around three percent) and its only a matter of time before they take the mantle of most valuable Valley company and hold on to it — at least as long as consumer spending and online advertising stay healthy. Not to say that Google’s executives are wasting their energies worrying about beating out Cisco in the market cap category — they’ve got plenty of _real_ competition from the likes of Yahoo, Microsoft and Ask.com. But is it just a coincidence that caption for the stock ticker lookup at Google Finance has two suggestions: “CSCO” and “Google”? Maybe. Maybe not. Technology Industry