This month Google released a new algorithm (the way they measure and track websites) that will actually penalize you for over optimizing your website. Google is always looking for the newest and best way to determine accurate search results for it's readers and those that simply optimize without actually providing relevant and fresh content may find themselves scrambling back to the top.
What they are trying to achieve is a level playing ground for those that optimize and those that just put out great content. Matt Cutts says, "“And the idea is basically to try and level the playing ground a little bit, so all those people who have sort of been doing, for lack of a better word, ‘over-optimization or overly doing their SEO, compared to the people who are just making great content and trying to make a fantastic site, we want to sort of make that playing field a little more level."
So does this mean that all the work you have done or paid for is going to harm your site?
That all depends on what you did and how far you went. This really is to elevate those with high-quality, relevant pages from pages that were just a collection of words about a subject. While many people really try and put out relevant content, some, and some SEO companies have just optimized the heck out of sites to where their hits are high but bounce rate is also extremely high, when you want it low (the amount of time spent on a website).
Google is constantly trying to find the freshest information that fits the searchers criteria best. Does this mean that those keywords and links you added to pages will harm your site? Probably not unless you jammed 30 keywords in a 200 word document and linked to and from it 50 times.
This penalization is for sites that do just that; over-optimize with no real meat to the site. So how do you make sure your site is not targeted in this over-optimization penalization? Here are some things to consider:
1. Make sure your site's name and domain are specific. Don't use generic terms too much such as www.housesforsale.com. Make your domain (if you can) specific to your area and your niche.
2. Keeping the "home" page just that, not a specific keyword. Google doesn't need to see your keyword everywhere to rank you for that keyword anymore. (can I just say that I'm guilty as charged?)
3. Using your main keyword over and over and linking it back to the home page numerous times in one page. While once is good, 5 times is bad. Directing people back to the main page is not a bad idea and using your keyword keeps the bot focused on your topic, doing it too much will start to raise red flags.
4. Linking a page to itself. This is technically old SEO tactics but Google will really start cracking down on it. Don't bother linking a page to itself using its keyword in the content. This is redundant and Google may start to rank this page lower because of it.
Should you be worried? Probably not, especially if you try and offer relevant content on a fresh and new basis for your clients. Over-doing it for the sake of SEO will start to look suspicious. Stay on top of the search results by know your competition and how you're ranked and you should do fine. Although we may be seeing a lot of new sites pop up because of this.