I'm checking out my sites and some of my PR5 for "domain.com" have PR4 for "domain.com/index.htm." Knowing that... shouldn't I do a 301 redirect from "domain.com/index.htm" to "domain.com"? That way I only have 1 home page instead of two and all my PR will go to one page?
If the default you're using is index.htm, then yes, it's the same. Doing a 301 redirect would cause a 'max URL exceed' error because you would be redirecting to the same site over and over again. It should be fine as is.
They are not the same page to search engines. Now, sure they're smart enough to know that any page with an index name is likely the homepage for that directory and not give you any dupe penalties, but that will cause the pagerank to be split etc. and will likely affect serps. The right thing to do is have all your internal links pointing to the same place, and all the links into your website going to that page. The typical way is for all your homepage links to point to "/" and stay far away from pointing to a file when you can point to a folder instead.
Right... all the links on my site point to "/". But at one time I may have had a few links point to index.htm (back 4 or 5 years ago when I started some sites). Also, some people must be linking to the "index.htm" page instead of the root. I just thought there might be a way to rewrite the index.htm to the root. I'm checking with ISAPI_REWRITE (I have a dedicated windows box) and I think that may work. But like fsmedia said, it may cause an error.
Well, I got it working I'm ussing IIS 6.0 to redirect all domain.com to w w w.domain.c o m. I'm using ISAPI_REWRITE to redirect w w w.domain.c o m/index.htm to w w w.domain.c o m We'll see in 6 months or so if this has any effect on PR.
Also, with the new BigDaddy update, canonical URIs will be understood so google will index 'domain.com', 'domain.com/' as the same URI, not diferent ones.