This is directed to 2.7 development/feature request, I think :) If it is already there and I just can't see, have pity.
With the proliferation of categories, tags, custom fields and what will come next, there's a chore that has to present itself more than just to me:
deleting all posts with a certain field value (eg. tag="delete me")
Not understanding the structure and relationships of the WP database, I thought I'd just run a straight delete query against the Posts table. But then of course I realized I'd left behind a whole lot of stuff in postmeta, term relationships and I honestly don't know where else.
Would it be a big job to add a "query by example" Delete Posts function in the Manage Posts section that would allow the admin to select the field they want to use ("Tag,Category,Post Date) and an input box for the value to match on. I'm thinking similar to PHPAdmin. The key with this feature would be the code would know about everything to delete, not just the records from the posts table.
I have also discovered some plugins that allow you to delete all posts created by them, actually only delete the posts table entries. And some plugins (RSS feeds including the ones included with WP dashboard) write a bunch of content directly into the Options table. For some of them uninstalling or removing posts does not remove those Options table entries.
This all came to my attention because I have a two WP installs that I use to experiment a lot with plugins and themes and trying to learn how to edit the php files without blowing up the universe. One them used up its 100 Meg disk quota from my host yet it had only a few thousand active posts. Almost the whole db was filled with left-overs from my excessive experiments. Of course in this case it is easy to simply empty the database and start from scratch, but I can't imagine having to deal with it on a production install, even for a thousand posts. From what I can tell you would literally have to sit and delete each post individually to ensure it was properly cleaned up?