I'm updating a site that is currently static html (i.e. index.html). I'd like to pull in blog posts into the page and only know of SimplePie to accomplish this.
Question 1 - If I update the site from .html to .php is there a hit in SEO while the Search Engines re-index?
Question 2 - Is there a way to use Server Side Includes to include a .php file of my SimplePie results, or another way to pull blog posts directly into a .html file?
I'd appreciate advice.
For question 1 - no, not necessarily. You can use apache's mod_rewrite to process the old HTML pages as php scripts, and you don't need to change URLs. For question 2, it depends how your simplepie results are loaded, but PHP can include another file fairly easily. Can you provide more detail about the file being included?