very good example of this is see this post...this is not his signature below he made it look like one
White or black hat SEO still all narrow down to one logical answer, are you gaining legitimate internet traffic? Using white hat SEO involves some real SEO work while black hat SEO methods only gain you money but in the long run you are penalized for this method. I read an article that was on how to promote your blog or website which SEO is doing for you in the long run - check it out here: fukkiit.com/How_to_promote_your_Blog.html
For SEO consultants who practise white hat SEO, they tend to produce results that last a long time. Black hat SEO techniques may get a website to rank well initially, but the site will eventually be banned either temporary or permanently once search engines discover what they are doing. So it is very important for you to know the best practices in the SEO industry and make sure that the SEO agency that is handling your account uses techniques that conform to the search engines' guidelines and involves no deception. White hat technique is generally summed up as creating content for users, not the search engines. The content that is created should be easily accessible to search engine spiders, rather than intending to trick the algorithms from its intended purpose. So, the general rule of thumb is to stay on the safe side by creating content that is relevant to your target audience. Search engines value relevancy - they will definitely want to rank a site higher their organic listings if the content on the site is what searchers are looking for. Black hat technique usually involves techniques that attempt to improve rankings that are disapproved by search engines, or involve deception. One common black hat technique is to use hidden text, either as text coloured similar to the background of the website, or positioned off-screen. Another common technique known as cloaking is to load a different page depending on whether the page is accessed by a human or a search engine spider. Search engines will penalize sites which use black hat techniques, either by reducing their organic rankings or even eliminating them from their database completely. This is a very costly mistake on the business point of view as you will lose out a lot of grounds as your competitors are enjoying free organic traffic from search engines due to their high rankings for major key phrases. Therefore, it is very important to make sure that your SEO agency is moving away from black hat methods. You will not want to be blacklisted by search engines which will translate into loss in sales and profits.
I think a lot of methods that most of use would be considered "gray hat." There's sort of a middle world where it's not spamming but it's not 100% what Google would like us to do either.