For sure, About Drupal is a more helpful link than http://drupal.org/node/1; with the first I know what the topic of the linked page is, while with the latter I only know the domain name for the server hosting the linked page. This is even more true when the page title uses more words, like Ways to get involved, or Let users cancel their accounts.
As for approving a suggested edit like that, it depends from the fact there are other things that should be changed. If the author of the post wrote i instead of I, kept using the comma where it should not have been used, and those things don't get changed, then I would reject the suggested edit.
If then the user would start suggesting similar edits for more than 6 posts in few time, then I would also check how much of the post gets changed. I would think the user is trying to get some reputation without answering, or asking questions.
While the change can make the post more useful, the fact the link has not been edited so far means it was not so urgent, which also means there is not a really necessity to change the link used in the post, and do it for any other post in few time. It would be different if the original link is broken, and who suggests the edit knows exactly the link to use.