The Web Page
Page Title - Does your title explain what the page is? Is your page title descriptive? This is what will show up if someone bookmarks your page, and at the top of the page.
Content - Is your content compelling? Is it interesting for more people than just you and your friends and family? People come to Web sites for information. If your Web page doesn't have any, then they won't come back.
Page Length - Have you thought about how your page will look on different browsers? If it is too long, people won't want to scroll to read it, but if it's too short, it won't have enough information to keep people on the page.
Images
Size - Are your images smaller than 12Kb? If you must have an image larger than that, show the reader a thumbnail (a smaller version of the image that was resized by a paint program not the browser) and allow them to decide if they want to download it.
Links - Are your image links clearly links? It is also a good idea to have image maps with text links elsewhere on the page. This makes the links more accessible.
Quality - Do your images serve a purpose? If you add it to the page, then think about what it lends to the page. For example, these check marks are here to emphasize the "checklist" nature of this page.
HTML - Does your image tag have all necessary HTML? This includes the width and height, and the alt text.
Links
Text - Do you link to descriptive text rather than boring words like "click here"? The biggest problem with navigation on the Web is that readers don't know where they are going.
Annotations - Do you describe your links? If a page is good enough to link to, it is good enough to have an explanation.
Quality - Do all of your links go to active pages? If you maintain a site on the Web, you should spend time every week making sure that the links work. There are many validators available to check your links with.
General Issues
Feedback - Does your page have a mailto or feedback form on it? If you are putting up a Web page, feedback from your readers can help you make it better. Chances are, the spammers will find you either way, and hiding your identity just makes your page look less real.
Last Updated - Does your page indicate when it was last updated or what is new? If you update your page frequently, this helps readers determine if they will find value in reading your site again.
Valid HTML - Does your HTML meet HTML standards? While it isn't always vital that you use only HTML standard tags, you should use correct HTML, and use browser specific tags only when you have adjusted for the differences on different platforms.
Correct Spelling and Grammar - Are there any spelling or grammar errors on your page? If there are, you should fix them. Simple typos can destroy the credibility of an otherwise wonderful page.