When I do URL rewriting does it make a difference to search engine if the URL looks like this http://www.sitename.com/content/ and not like this http://www.sitename.com/content.html Will pages with the first option rank well?
It is funny you use that. I do not understand how search engines can pick that up or how google is able to pass page rank off to it, but they do. I perfer .html though because that is the easiest for spiders to read.
Well I dont use it but I have seen people use it to make nice URLs for dynamic generated pages and these pages do get PR. I just wondered if they will rank the same or not?
Yes, they rank the same. But you need to make sure what you're linking to. You'll run into Canonical issues if you don't. For instance, their are too ways to link to this sort of page: www .yoursite.com/content/ Either: www .yoursite.com/content/ Or: www .yoursite.com/content/index.html (or .php) Whichever way you choose, make sure you are consistant and do that throughout your site's linking structure.
I've had excellent results with the non-html version of URLs, except it should be of the form www .yourdomain.com/content and not www .yourdomain.com/content/ (with slash at end)