I heard that complicated URL’s are not favoured by Google’s Search Engine.
I think that URL structure matters far more for click-through than SEO - but the ability to contain keywords in a URL properly isn’t to be ignored either.
Is everyone doing a MOD Rewrite?
Basically, yes.
Currently I mainly work with .htm pages only. What is the situation and best practice with using PHP pages?
I will be converting many pages to PHP in the near future. What is the best practice in terms of search engines?
I think that most people are using some form of “pretty url” anymore. http://example.com/my-page-name or the like. Whether you do the same is up to you - I’d read up on the advantages and see if you think it’s worth the time.
Obviously, when the user is in-application, you may end up using the URL for something more complicated - but for just the regular page URLs, there doesn’t seem to be a reason anymore to make it particularly complicated in many cases.