Four Hours Later... I have over 650 5mb xml files and it's still rebuilding the Tags for the sitemap. We used to have a system that auto-generated tags and as a result, we have a LOT of tags across 35k discussions. When I woke up this morning, I had a 3 gig sitemap folder and the rebuild tool had timed out at some point.
So, I wiped the sitemap folder again, changed the XML Sitemap Generation option to exclude tags, then rebuild the sitemap with the Rebuild Caches tool. This time it took only a minute and my sitemap folder was only about 3 megs.
I guess I want to know if this is normal? Should I reinstate the tags and just not worry about the size, or should I keep excluding the tags? Do the tags make any appreciable SEO difference or does Google ding me for having an insane sitemap folder?