When creating a node (e.g. Basic page) If you leave the summary textarea blank it uses a trimmed value of full text in the body textarea as the summary.
When using [node:summary] token as the default token for the meta description, it should pull a trimmed value from the body textarea.
1. Once you fill in the summary, it does indeed create the meta description
2. changing the token to [node:body] for the meta description and flushing cache does create a meta description (although too long)
I guess what I am requesting is the ability to define [node:summary] in the default meta description for content and if nothing is in that field, it pulls a trimmed version of the body field.
This is a core bug. Interested people should help work on the patches in #1300920: The [node:summary] token does not output anything for body fields without a manual summary.
There is also a patch you can use for Drupal 7: http://drupal.org/node/1300920#comment-6779546