I've submitted a sitemap to GWT and things are starting to index as shown under the Crawl → Sitemaps menu. I've also confirmed indexing by doing a Google "site:" search.
However going to the Google Index → Index Status menu shows 0 pages indexed.
What is the difference between the Sitemap page's count of indexed pages and the Index Status count? There seems to be no simple way to see the total number of pages indexed. The only way is going through each individual sitemap index and summing up each individually (which is not possible as I have a lot of indexes).