Last year, Google announced that it started to index SVG files, but the results were only returned by the web search engine. "SVG is an open, XML-based format for vector graphics with support for interactive elements. We're big fans of open standards, and our mission is to organize the world's information, so indexing SVG is a natural step. We index SVG content whether it is in a standalone file or embedded directly in HTML," explained Google at that time.
Now you can find SVG files in Google Image Search by restricting the results to this filetype in the advanced search page or by using the filetype operator. Here's an example: [molecule filetype:svg]. If you restrict the results to Wikipedia, Google returns 57,300 SVG files.
Most browsers can render SVG markup, but there are at least two important exceptions: Internet Explorer (IE9 will add support for SVG) and Android's built-in browser.