TIEdupedeleter Simple Duplicate Post Deleter

Yes, it is. Nothing new is added, but bugs will be fixed. All new functionality goes into TIEtools.

No, it just checks titles.

Apparently not, according to someone who tried it. It was never designed for that, so I'm not surprised.

Yes. Either deactivate the plugin or use the power setting on the options page. The power button doesn't actually remove the scheduled job, but it makes the plugin skip all the checking functionality.

At most once per hour. You can change this in the do_TIEdupedeleter_activation function: switch the value 'hourly' to whatever suits you (and will work with wp_cron).

Since dates can be changed through the WordPress interface, the plugin uses the post ID in the database, not the published date or anything else. Whichever copy was created first/last, that's the oldest/newest (respectively). In SQL terms, it does a min(ID) or max(ID) check.

Yes. Only duplicates where both (or all) copies are in the categories being searched will be affected. i.e. If a post in an included category has a copy in an excluded category, it won't be removed.

The include/exclude option is a radio button, so it can't be set to "neither". However, you can switch off the category filter for each expiration method. Setting the categories to include (or exclude) to "0" and clicking the radio button efffectively stops all category filtering as well.

The parent category will be taken into account and all sub-categories will be ignored. Yes, this makes entering a dozen sub-cats a long process, but it gives you much finer control over precisely what is included or excluded in the expiry process.

You can go to Posts -> Categories, click a category name and look at the URL, which includes a "tag_ID=xxx" part, showing the category number (xxx). Or you could install and activate the Reveal IDs plugin, which adds a column on the categories page to show the ID number of each one. Much easier. The plugin URL is http://wordpress.org/plugins/reveal-ids-for-wp-admin-25

No. The plugin only handles categories at the moment.

No. That's just way too complex to do without a load of post lists and manual clicking. The plugin is designed to be easy and simple.

The very first time the queries run, it might. This is especially true if you have a lot of posts. In testing, it caused a delay of a few seconds in page serving the first time it ran. After that, I never noticed a delay again.

You're reading it. The plugin code is also heavily commented to help you find your way and there's the plugin's homepage at http://www.setupmyvps.com/tiedupedeleter

There are a few tests which are really easy to add, the most obvious of which is duplicate post content. That would be an additional option, to allow for either/both checks. I guess the plugin could also offer the option of determining the newest and oldest post by publication date. After that, the only additions I can think of go into the area of fuzzy logic matching for similar posts rather than exact matches, which is really beyond the scope of the plugin.