I would recommend a limit of 50-75 links per page. I would also suggest that you list the links in order of importance, so that the most important links get crawled, in case a search engine has a lower limit.
Image maps may be pleasing to the eye, but search engine spiders don’t like them. They cannot crawl links contained within the image maps. Therefore, if you use image maps, I highly recommend adding HTML links elsewhere on the page for search engine spiders can crawl.
A splash page / screen, is the first page of a site used to capture the visitor’s attention for a short time as a promotion or lead-in to the real home page.
Most splash pages usually consist of nothing more than a corporate logo, or an attention grabbing visual or multimedia effect, such as a Flash applet, promoting the site's brand image.
The splash page typically has a link to the “real” home page, but is sometimes set to automatically forward the user after a certain amount of time has elapsed, or when the multimedia effect has finished playing.
As far as search engine optimization is concerned, most splash pages rank poorly, simply because they do not have sufficient text for search engines to index. Quite often, the only text on a splash page is a link to the real home page.
As such, I do not recommend the use of splash pages.
Whenever I see a splash page, I ask the question, 'What does this do for the site?' More often than not, the answer is nothing, as I simply click though to the real home page, or back out of the site, if the page is taking too long to download, and there are no options to bypass the splash page.
It is rare than I ever wait to watch the multimedia effect, and I cannot remember the last splash page that made a lasting impression on me.
So, before you decide to create a splash page for your site, ask yourself this question, "What am I trying to achieve with a splash page?"
Web directories like the Open Directory Project and the Yahoo! Directory rank their directory listings alphanumerically, following the order of the ASCII (American Standard Code for Information Interchange) alphanumeric character set.
So for example, a title that begins with the letter A (#65 in the ASCII chart) ranks higher than one beginning with the letter B (#66 in the ASCII chart), which in turn ranks higher than one beginning with the letter C (#67 in the ASCII chart) and so on.
Obviously, titles usually contain more than just a single letter. If two site titles both begin with the same letter, the next letter is taken into consideration, then the next, and so on. Therefore a listing title that begins with a lower number in the ASCII character set will be ranked higher in the Yahoo! Directory and Open Directory index.
Listings near the top of a page are almost always going to receive more traffic than those at the bottom. Therefore, alphanumeric rankings can play a big role in determining the amount of traffic a listing receives in the directory.
Considering the popularity of the Yahoo! Directory and the fact that many search engines, use the Open Directory listings, it is no wonder that web marketers have long taken alphanumeric rankings into consideration in selecting their site title.
Some marketers went one step further and began adding numbers and other special characters, such as the hash symbol "#" (#35 in the ASCII chart), number 1 (#1), and even the exclamation mark "!" (#33 in the ASCII chart) to the beginning of site titles.
! ! ! ! ! ! ! Lucky 7's Online Gambling Guide
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Can you believe that these are examples of real websites using this technique in the Yahoo! Directory?
I do not recommend this technique. It “may” push your site to the top of the rankings, if the web directory editor reviewing your submission accepts it. However few people will remember it, and unless they bookmark your site, it does nothing for you in terms of brand awareness. So unless the visitor clicks on the same link again, they’re unlikely to return.