Recently, I received an email question wanting to know about keyword density, asking questions like how do I deal with it, is it still a factor, and how important is it. As with most things in SEO, the answer is … it depends…

Sherman, set the Wayback Machine to the Interwebz circa 2001 …

Google mobile search and Google search are two different animals and understanding more about both has become a necessary evil. Currently, the results returned when doing a search on a mobile device can vary greatly from those done on a desktop (SEORoundtable)

Microsoft announced that it has expanded negative keyword limits in adCenter. This should be of particular interest now that Yahoo and adCenter are coming together.

If you’re not familiar with negative keywords, advertisers can prevent their ads from appearing in response to certain search queries using negative keywords (specific words or phrases that help prevent ads from being displayed to customers who are unlikely to click).

Google said this week it is launching its broad match modifier tool for AdWords globally after a successful beta test in the UK and Canada.

There is a new Keyword Diagnosis option in the Keywords tab in AdWords. This can give advertisers detailed diagnostic info for multiple keywords at a time.

"Whether you have ten keywords or ten thousand, making sure your ads are showing is a top priority," says Miles Johnson of Google’s Inside AdWords crew.

I’ve said it before and I’ll say it again … there is no more important step in the SEO process than keyword research. One could make a compelling argument for link building or for architecture or for copywriting but at the end of the day – ranking highly for keywords that either don’t convert or which you close up shop waiting to rank for isn’t going to help too terribly much so in my opinion – I’d put keyword research higher in importance.

Google announced today that AdSense for Domains is now using optional keyword hints more often. Keyword hints are provided by the user, who enters keywords into a field to assist Google in the targeting of ads for potentially ambiguous domains. Google’s Randy Heath explains:

Google does not use the "keywords" meta tag in its web search ranking. Google’s Matt Cutts explains this in a Webmaster Central video. This is not breaking news, by any means, but there are a lot of people out there that still put a lot of stock into this.