Better WordPress Google XML Sitemaps by OddOneOut is the first WordPress XML Sitemap plugin that comes with comprehensive support for Sitemapindex and Multi-site.
Sitemapindex Support
Sitemapindex, as its name suggests, is one kind of sitemaps that allows you to group multiple sitemaps files inside it. Sitemapindex, therefore, gives you many benefits, such as: possibility to bypass the 50,000 URL limit (you can have 10 custom sitemaps, each has 10000 URLs), or possibility to make the generation time much faster (because each sitemap is requested separately and is built by its own module), etc.
Multi-site Support
Each website within your network will have its own sitemapindex and sitemaps. For sub-domain installation, your sitemapindex will appear at http://sub-domain.example.com/sitemapindex.xml. For sub-folder installation, your sitemapindex will appear at http://example.com/sub-folder/sitemapindex.xml. And of course, there’s always a sitemapindex for your main site, available at http://example.com/sitemapindex.xml. If you choose the sub-domain approach, each sub-domain can also have its own robots.txt.
Custom sitemaps using modules
The unrivaled flexibility this plugin offers is the ability to define your custom sitemaps using modules. Each module is a actually .php file that tell BWP Google XML Sitemap how to build a sitemap file. You can extend default modules or create completely new ones. This plugin also comes with a convenient base class for developing modules with easy to use and thoroughly documented API. Since modules can be defined by you, there’s no limitation what a sitemap can have (for example you can bypass the 50,000 URL limit, as stated above). There’s one limitation, though: your imagination ;) . Oh, did I mention that you can even use module to create another sitemapindex?
Detailed Log and Debugging mode
Developing modules needs debugging and this plugin makes that so easy for any developers. There are two kinds of logs: sitemap log and build log. Sitemap log tells you what sitemaps you have and when they were last requested/updated while build log tells you what’s going on when a particular sitemap is built. The debug mode helps you trace errors in modules conveniently!
Plugin homepage: http://betterwp.net/wordpress-plugins/google-xml-sitemaps/
Download: http://wordpress.org/extend/plugins/bwp-google-xml-sitemaps/
