You are welcome to look around. You will have to register before you can post a message, create a blog, chat live with our members, or add a site to our directory.
I find that most of my blog articles are anywhere from 400-600 words long, and this seems like a great range where users aren't bored and staring at walls of text, but Google still finds enough content to index.
What is a good number of times to mention your keywords in your article? Clearly you can't just repeat the keywords over and over, but you should drop them in like a sneaky SEO ninja
Try to go for seasoning of keywords, not spamming (density is a decent word for spamming).
You can use as many different keywords as you find relevant to the articles. Because it'd get you in search engines for many keyword searches, longtail phrases and natural content for readers. It works far better than repeating same keyword.
It's funny but looks like Google still penalizes excess of everything (keywords here) and that includes hidden text too.
That's because they are penalizing people who are trying to manipulate search results in an obvious manner. Excessive use of keywords and hidden text are outdated methods used by less knowledgeable site owners who still believe that these methods work.
In a 400 to 500 word article, it is a good idea to mention the keyword theme for the page once or twice in the text, but packing keywords into the text is bad idea. You should always write content for your users, but do not completely ignore what search engines are looking for.