I've read where the number of indexed pages is a factor in SEO. I currently have several long pages that could be broken into shorter pages and spread out a bit. Would that be better? Another question is if I do break them into shorter pages will the SE's see it as new content and like it or just recycled/duplicate content and not like it?
It would not count as duplicate content if of course the previously indexed page contains only half the article and then there's links to the rest half. SEO wise, it doesn't actually matter that much..having tons of indexed pages is good but the goal is to make sure all your pages are indexed...it doesn't actually matter in the actual SERP of any keywords. However, adsense wise, splitting articles is a good idea.. It just depends on the length of the articles I gues..if it's 2000 words you might as well split it, if it's 750..not worth splitting it..IMHO
Depends how long the original article is. If you can break it up into 250 to 300 word articles then it'll be more pages for Google to index and probably a better chance of you getting some more AdSense clicks. I forget where I read it, but after about 750-800 words on a page, your web visitors tend to lose interest. You could also split the original article into several smaller articles and then reword the new articles for a fresh approach. Chances are your returning visitors will read the smaller articles too even if they read the longer, original version.
Some of the pages I have are really loooooong and could easily make 3 or 4 shorter pages and nearly double the number of pages for my site. So that would be good right? Next question is since the current pages are "3rd tier" pages should I link to all of the newer segments from the original page so that the spiders see them more easily for indexing purposes? BTW - the site in question currently has all pages fully indexed by the big 3 SE's.
I would say that it depends on the words you are targetting. There is obviously no proof of this, but I have found that easy to target niche keywords are fine with a one page, however - if you are targetting super competitive keywords then the number of pages in your site plays a significant enough factor to warrant splitting them up imho.
I tend to stick to medium sized pages. 300 words to 750 words. I can target many more long-tail versions of my main key phrases this way. I think. On other sites I go with short 200-300 word pages. Only because topic makes it hard to write more than that. Those pages target very specific terms with less long tail versions. Breaking up an article to 2 or 3 pages usually makes page 2 or 3 one level deeper in the linking structure. This makes it more likely they do not get indexed. Unless you do some tricky interlinking from other parts of your site to ensure these deeper partial pages get crawled, and a bit of PR passed their way, so that they can pull search traffic on their own. Otherwise keep your article longer. If your worried about a longer article making the surfer loose interest then work on optimizing ad placement so if they do loose interest half way in they may click an ad instead of the back button. But don't stuff the long page full of ads or they wont read anything to begin with. Its a bit of a balance.