We made transitioned out website to HTTPS. We also now use nearly AJAX to load almost all the content. Therefore all URLs of existing pages have changed. We used 301 redirects as recommended and we have implemented Google's crawlable AJAX specification.
We thought that maybe our rankings be worse for a month and then they would recover. Google's search results are still much worse for us than before these changes. Most of the content (artist profiles) isn't indexed anymore. For example, in the submitted sitemap only 3 of 450 URLs are indexed. Before the changes, almost all URLs were indexed.
Does Google's AJAX crawling and indexing work together with HTTPS? It looks like it should work, because I see Googlebot active in my server logs.