Will infinite scroll will be a problem for search engine optimization (SEO)?

Infinite scroll would be a problem if all of site’s content is accessible only from such pages, then search crawlers wouldn’t be able to index your content. But.. except on front page, all posts and pages are accessible through: category pages (you can switch grid layout for categories globally or only for selected categories), tag pages and date archive pages.

Let’s step away from this theme for a moment. Here problem could be that a lot of your site’s pages with the similar (or even same content) could be indexed (remember that each post is on a category/tag page for each category/tag that it belongs to). And that lowers the search rank of all of those pages. That’s why popular SEO plugins (like SEO by Yoast) offer an option, in their settings, to prevent search engines to index your category and tag pages.

So your posts should be indexed well. Furthermore, if you plan to optimize your site you’ll probably generate an xml map of your site, often that’s also a feature of a popular SEO plugins, and register it at Google Webmasters Tools service (and similar service for Bing and any other search engines). Basically, xml map contains URLs to all of your site’s content and by submitting it to Webmaster service your telling crawlers of that search engine to index all of those links. Also, using those services you’ll be able to see which of your site’s pages are indexed and so on.