scary: if you visit google.com with Google Chrome, you can search by voice, even from your desktop computer (if you have a microphone and many laptops do). The idea is cool, but this seems like a huge security/privacy problem!
Not really; websites may ask for speech input (using the 'speech' attribute[1] in certain HTML tags), but the browser keeps full control of the feature, so they can't enable it themselves without your intervention.
Of course, since Google controls Chrome, they can control that too, but on the other hand, they already could - any native app can record sound. The solution for that is simply not installing applications you don't trust.
