I've been using NextGEN Gallery plugin for a year now with thousands of images. But one big flaw is that Google Images simply does NOT seem to like this plugin for whatever reason.
All of my NextGen images are tagged, each have a title and description, all have the keywords in the file name, etc. Yet Google absolutely refuses to index them. Images that I post with the default WordPress gallery system are indexed by Google Images within hours, so I would say it is definitely an issue with the plugin rather than my website.
The only way I've had any sort of success with Google indexing NGG images is by using the included NGG WordPress widget and having it display random photos from my NextGEN Gallery. That is obviously not an ideal solution though and it would take forever to index my thousands of images using that method.
When I last looked into this a few months ago I read a post about an image sitemap feature coming in the next version of NextGEN Gallery. It doesn't seem like that ever got released yet, but I don't think that would help anyway because Google is finding the posts/images, just choosing not to index them for whatever reason.
I'm wondering if anyone here has found a solution or tips to improve the SEO of NextGEN Gallery? This plugin is perfect for my needs but if nobody can find my images from search engines I will have to start looking into alternative solutions.