We have a good question from Majico in London, United Kingdom. Majico asks, "Now that Google can call JavaScript links, what is going to happen with all those paid links that were behind JavaScript code, will Google start penalizing them?" So I answered this at XMX Advance Step in Seattle, but let me answer it again.
Google has gotten better and better crawling JavaScript to the point where URLs that you might have put in JavaScript, and you thought we are going to be crawled--could possibly be crawled and indexed now. It turns out that the vast majority of people who do JavaScript sort of links or typically ad networks and we handle all the common cases where, you know, there's JavaScript being used to serve up ads.
So, all the common ad networks--we pretty much already know about, and already handled very well, and then, any paid links that are done--that were using JavaScript code, what you can do is you can use a no-follow attribute even within your JavaScript code.
You can always use a robust.txt and block out a URL that--for example would be included or a URL redirection that would happen, and then that way Google call the page that blocked by robust.txt, would we can't follow the URL redirect or we can't include that code from JavaScript for example.
So those are some safe ways to do it. We find that the vast majority of paid links are typically not done with JavaScript, they're typically, you know, completely straight text links and things like that, so that's where we have been spending the vast majority of our time.
But if you do have links that are paid and are currently in JavaScript, it's a good idea to just check them and say, "Okay, do I have something for example that's blocked out by robot.txt so
that search engines won't accidentally crawl, execute, see that JavaScript, and find new links as result of that JavaScript?"
So, we're not currently penalizing, we may down in the line start to look at that, but in my experience it hasn't been a big issue at all because the vast majority of these links are--for example, well known ad network and things that we already handled very well.
So, as always, if you're selling text links, just make sure that those links don't flow PageRank, that they don't affect search engines, and there are number of very easy ways to do that, and ways that have been the same ever since we talked about paid links using robust.txt, using the no-follow attribute, all that sort of stuff.