Unhandled Perception: Search Engine Optimization (SEO), what little I know

I have learned a little about SEO over the years and have had some good results with some of my clients websites and my own. I wanted to share a quick run down of some various things I have learned.

Random thoughts:

Make sure pages are well structured and the code is as clean as possible (XHTML compliant helps with this). Google only reads the data of the page and well structure helps it identify what's important on a page.
Don't use Flash and expect it to help in anyway. No spider can read the contents of a Flash file and therefore all is ignored.
Make use of H tags as H1 tags will be read as the most important information on a page in the body (this is below page name, URL, and title).
The higher up in a page the information the more important / relevant it will appear.
Don't rely on images to convey important information - Images can't be interpreted by Google. If images are used make sure you have well worded ALT tags and don't make them too long, short and sweet.
Don’t use links that say Click here or other verb type actions. Use links that are descriptive to where its going and what will be accomplished by clicking the link.
Try and get yourself into the DMOZ (www.dmoz.org) - this helps you get into lots of other search engines which in turn helps in Google. DMOZ is a open database of websites used by lots of search engines including Google. This also will help you get listed in Google's regional directories.
Don't over do meta tags. Tags with more than 255 characters or abouts will be ignored. Plus Google does not use these for relevance - they look at content.
Come up with a list of keywords you want to be found on when search and make sure you page content uses these words. Make sure these words are used in the Title, ALT tags, and H tags (with H1 being important). This is referred to as keyword density, too much will get you penalized, too little and you will not be found - find the balance.
Get yourself onto any site you can - except links farms where you could end up getting de-listed from Google. Post answers in newsgroups, answers on forums, write articles, start a blog on your website, include a signature with your website where ever you post. Basically get your name and site out there.
Be consistent in your websites URL. Either use http://YourDomain.com or http://www.YourDomain.com and stick with it. Google sees these as different and you want one to get as much credit as possible for each page.
Make page names as relevant as possible.
Don’t make too many changes. It takes time for a change to affect your rankings or search results. Wait a couple months on a main change to take affect and don't be discouraged, it takes time.
DO NOT use under-handed methods for getting ranked higher like link farms, cloaking or lots of 1pt or text that matches the background color. This is a sure way to get de-listed.