One of the names I see for an update that has been done over 2011 is Google Panda. Now in 2012 the same panic and frustration is there but now it’s about the Google Penguin update. I don’t know what those updates are exactly but it’s something big.
Years ago people would use keywords on their website with the same color of text as the background it’s on. That way they keywords they want to be found for are on their site a lot and Google would like it to the search words people use. Back then it was a method that had effect. Now it still has effect but in a negative way. When Google finds out your doing this your site could be banned or how it’s called, sandbagged. You don’t want that because once your site gets a penalty it’s not that easy to get back from it.
There for it’s very important to follow what Google’s doing. Thing that work great for SEO right now maybe worthless or even harmful to you website in the future. Personally I think that when you start with SEO you have to focus on high quality. Don’t use easy methods to get a lot of backlinks all in one time but take the time, spread the link building and create a variety of backlinks.